Beverage preparation with pressurized liquid

ABSTRACT

A beverage preparation apparatus for preparation of a beverage from a capsule in a clamp assembly ( 30 ). The clamp assembly has a first clamp member ( 31 ) and a second clamp member, where the inner surfaces of the first clamp member and the second clamp member form a clamp chamber ( 33 ) for substantially enclosing and supporting a capsule ( 10 ) during beverage preparation. The second clamp member comprises a rigid peripheral frame ( 32 ) having a central void and a resilient layer ( 37 ) extending across said central void. There is a piston ( 36 ) positioned in the central void and resiliently coupled to the peripheral frame ( 32 ) to allow limited resilient movement of the rigid peripheral frame ( 32 ) relative to the piston ( 36 ).

RELATED APPLICATIONS

This application is a national phase filing under 35 USC 371 ofInternational Application No. PCT/GB2015/053194, filed on Oct. 23, 2015,which claims priority of British Patent Application No. 1418881.7, filedon Oct. 23, 2014, the entirety of which are incorporated herein byreference for all purposes.

TECHNICAL FIELD

The present invention relates to capsules, apparatus and methods for thepreparation of beverages by injecting water under high pressure intocapsules containing a beverage preparation ingredient.

BACKGROUND

Beverage making systems are known in which the beverage is made byinserting a capsule containing a particulate beverage making ingredient,such as ground coffee, into a beverage making station of a beveragemaking apparatus. The apparatus then injects water into the capsule,where the beverage making ingredient dissolves in, or infuses into, thewater to form the beverage. The beverage flows out of the capsulethrough a suitable outlet, which may be simply an opening or perforationin the capsule, or it may comprise an outlet tube that pierces an outletregion of the capsule. The capsule may incorporate a filter to preventpassage of solid components such as coffee grounds out of the capsule.Beverage making systems of this general type are described for examplein WO94/01344, EP-A-0512468 and EP-A-0468079 (all Nestle), in U.S. Pat.No. 5,840,189 and WO-A-0160220 (Keurig), in EP-A-0272922 (Kenco), inWO-A-2007093355 (Samar Technologies), in US-A-20110142996 (Kruger),EP-A-0710462 (Illycaffe), and in EP-A-0821906, US-A-20110000376 andUS-A-20110027425 (Sara Lee).

GB-A-2121762, GB-A-2122881, EP-A-0179641, EP-A-0247841 and WO-A-9905044describe capsule-based beverage preparation systems of the type that arenow widely used and marketed by Mars Drinks under the registered trademark FLAVIA®. An exemplary embodiment of a FLAVIA® capsule according tothe state of the art is shown in FIGS. 1, 2 a and 2 b. Similar capsulesare described in JP-A-4142266.

Referring to FIGS. 1, 2 a and 2 b, an exemplary FLAVIA®-type beveragepreparation capsule 100 comprises front and back sheets 110, 112 of aliquid- and air-impermeable sheet material permanently bonded togetheraround their top and side edges as described in more detail below. Thefront and back sheets are also bonded together along a bottom edge 120of the capsule, but this bond is releasable under the effect of heat orpressure inside the capsule. For example, the bonding of the bottom edge120 may be by means of a pressure-sensitive adhesive. Within the capsule100 is a folded web of filter material 130 bonded to the inside walls ofthe front and back sheets. The web of filter material supports abeverage preparation ingredient 150, such as ground coffee or leaf tea.The capsule 100 further comprises a nozzle 140 having tubular bore 142.The nozzle is inserted into the top edge of the capsule and bonded inairtight fashion to the front and back sheets, the nozzle being flangedto assist in locating the capsule 100 correctly with a beveragepreparation machine. The nozzle bore is initially sealed by a suitableairtight freshness barrier.

In use, the capsule 100 is introduced into a FLAVIA® dispensing machine,which comprises a clamp to grip the nozzle under the flange, and ahollow injector tube with a mechanism to insert the hollow injector tubeinto the nozzle bore, thereby piercing the freshness barrier. Thedispensing machine further comprises a source of hot water and a pump toinject the hot water through the injector tube into the capsule. Uponintroduction of the hot water through the injector tube and the nozzlebore, the beverage preparation ingredient 150 contained in the capsule100 is mixed with the hot water and a beverage is brewed. The bottomseam 120 of the capsule 100 opens under the effect of heat and liquidpressure, and the beverage passes through the filter web 130 and theopen bottom of the capsule and is collected in a receptacle located at areceptacle station situated directly below the capsule.

Referring to FIG. 2a , the sheet of web material 130 is folded to form aW in cross-section supporting the infusible beverage preparationingredient 150. Upon introduction of liquid through the liquid conduct,the liquid pressure causes the apex 132 of the W to evert to provide adownwardly convex filter bed as shown in FIG. 2b . The eversion effectassists in the rupture of the pressure-sensitive seal of the bottom seam120 to dispense a beverage brewed in the capsule. Further details andadvantages of the everting filter webs may be found in EP-A-0179641. TheFLAVIA® capsules and method provide beverages of superior quality, andfurthermore provide the advantage of avoiding cross-contamination of thebeverage preparation apparatus by successive beverages because thebeverage does not contact any part of the apparatus after preparation.

Current beverage dispensing systems of the FLAVIA® type are adapted toprepare beverages by injection of hot water at only slightly elevatedpressures, for example less than 1 bar gauge pressure. The capsules arenot designed to operate at higher pressures. In particular, injection ofwater at higher pressures could cause the filter to separate from thepack. However, the preparation of certain premium beverages, inparticular espresso coffee, requires water to be passed through thecoffee bed at a pressure greater than 5 bar and up to about 20 bar. Aneed therefore remains for capsules, apparatus and beverage preparationmethods for the preparation of espresso coffee and other high-pressureextraction beverages that also give the above-identified benefits ofquality and no cross-contamination.

It is also known to brew individual portions of espresso coffee fromindividual capsules of ground coffee. The capsules typically contain aportion of ground coffee, tightly compacted in a capsule having afrustoconical or oblate spheroid shape and formed from air- andmoisture-impermeable material. The capsule is inserted into a rigid,metal brewing chamber that is normally shaped to fit around the capsuletightly. The brewing chamber has a filter element in its base, means topierce the underside of the capsule, and means to inject hot water at apressure of 500-1500 kPa (5-15 bar) into the interior of the capsule tobrew espresso coffee. Espresso coffee brewing capsules and systems ofthis type are described, for example, in WO93/17932 and WO94/02059.

A drawback of existing espresso brewing capsules is that they areadapted for use with conventional espresso machines that have a rigidbrewing cavity dimensioned to receive a bed of coffee of specificdimensions and to apply the necessary pressure to such a bed of coffee.There is limited scope for varying the amount of coffee in the capsule,or for varying the degree of compaction of the coffee bed duringbrewing. A further drawback of the existing espresso systems is crosscontamination between the successive brews, since the beverage exitingthe capsule passes through, and therefore contaminates, the base part ofthe brewing chamber.

EP-A-0521186 describes a capsule containing a compressed beveragebrewing ingredient, such as ground coffee, for use in espresso-typemachines. The capsule is deformable to assume the shape of the cavity ofwhichever espresso machine it is used in. This removes the need for aspecial adapter to adapt existing espresso machines to the exact shapeand configuration of the capsule. Unfortunately, it also means that thecoffee in the capsule may be insufficiently compacted for optimalespresso coffee brewing. The problem of cross-contamination bysuccessive brews also exists for this configuration.

EP-A-0821906 describes methods of beverage brewing in which a vacuumpack containing a beverage brewing ingredient is placed in a clamp, hotwater is injected into the vacuum pack through a hollow needle, and thebrewed beverage is allowed to escape through a closing seam in thevacuum pack. The pack includes a movable plate opposite the closing seamof the vacuum pack that is used to compress the vacuum pack in the clampbefore brewing. The plates making up the brewing cavity are rigid, flatplates. These plates cannot apply high pressure to squeeze the vacuumpack without risk of bursting the pack.

WO-A-0219875 describes an apparatus for the brewing of a beverage bytransmission of an aqueous fluid through a capsule (capsule) containinga beverage brewing ingredient, said apparatus comprising: one or moreinjectors to inject the aqueous fluid into the capsule during saidbrewing; and a clamp for the capsule, said clamp comprising one or moremembers that are movable to open and close the clamp, said membershaving inner surfaces which in a closed position of the clamp define acavity adapted to substantially enclose and support the capsule duringsaid brewing and further adapted to define a beverage exit pathway in alower part of the cavity, and wherein the inner surface of at least oneclamp member comprises at least one deformable region mounted on asupport that is movable while the clamp is in said closed position,whereby the shape of said cavity or said exit pathway can be changedwhile the clamp is in said closed position to provide a desired brewingconfiguration of the capsule. The capsule is suitably a capsule of theFLAVIA® type, optionally with modifications.

WO-A-2012175985 describes a beverage preparation capsule containing abeverage preparation ingredient for the preparation of beverages byinjecting water under pressure. The capsule comprises a body having sidewalls formed from one or more substantially air- and liquid-impermeablesheet materials defining a chamber containing a beverage preparationingredient and further defining an outlet channel having an upstream endin fluid communication with the chamber for escape of beverage from saidchamber, wherein at least a region of the outlet channel is filled by afiltration material for filtering the beverage escaping from saidchamber. Suitably, the filtration material is in the form of two or morestacked layers of filtration sheet, for example formed from a singlefilter sheet having first and second edges bonded to opposite side wallsof the body above the outlet channel, respectively, the sheet beingV-folded or W-folded between the side walls to form said stacked layersin the outlet channel.

FIGS. 3 and 4, show a capsule as described in WO20121751585. The capsule150 is formed from front and back sheets 151,152 of flexible sheetmaterial bonded together by a permanent heat (or ultrasonic) seal alongside edges 153,154 and top edge 155. An injection nozzle 156 is bondedbetween the front and back sheets in the center of top edge 155 inair-tight fashion. A permanent heat seal 170 also extends transverselyacross the capsule spaced from the bottom of the capsule to define thebottom of the beverage ingredient chamber 162 but with a central gapdefining an outlet channel 157, as shown in dashed lines in FIG. 3. Thebeverage ingredient chamber is substantially filled with an ingredient175, such as ground coffee. The permanent heat seal further comprisescurved downward extensions 158, 159 on either side of the longitudinalaxis of the capsule below the outlet channel 157 defining the lateraledges of the downstream chamber 160. The bottom edge 161 of the capsuleis sealed with a linear heat-releasable adhesive seal providing afreshness barrier prior to use of the capsule. The width of thedownstream chamber is intermediate the width of the beverage ingredientchamber 162 and the narrower outlet channel 157.

A filter in the outlet channel 157 is provided by a single, rectangularsheet of filter material 171 that is V-folded with opposed edges 172,173bonded to the inside of the front and back sheets 151,152, respectivelyin similar fashion to the bonding of the filter sheet in the prior artcapsules of FIGS. 1-2. The edges 172,173 are bonded to the inside of thefront and back sheets 151,152 at a location well above the outletchannel 157. The V-folded filter sheet extends downwardly through theoutlet channel 157, with the bottom 174 of the V located within thedownstream chamber 160. The outlet channel 157 is thereby filled by adouble thickness of filter sheet material. It is noted that the V-stripof filter material extends across substantially the whole width of thepack, whereby in regions where the V-folded filter sheet overlaps thepermanent heat seal, the permanent heat seal is formed through theV-folded filter sheet so that the front and back sheets 151,152 and theV-folded filter sheet 171 are all bonded together. This is facilitatedby the use of a filter sheet containing thermoplastic fibers, such aspolypropylene fibers. However, the filter sheet is not bonded to thefront and back faces in the outlet region, nor does it extend into thereleasable seal region 161 at the bottom of the pack.

In use, the beverage preparation capsule of FIGS. 3 and 4 is insertedinto a clamp assembly of a beverage preparation apparatus such that anoutlet of the capsule is pinched between the clamp members in the outletregion to provide a flow restriction at the outlet and maintain highback pressure inside the capsule body. Water at pressures of 5-15 bar isinjected into the capsule in the inlet region to produce a beverage inthe capsule; and the beverage escapes through the outlet region.

Channelling of liquid through the compressed bed of beverage preparationmaterial during brewing may occur when preparing beverages usingcapsule-based (i.e. capsule-type) systems, especially where relativelyhigh pressures are required such as in the preparation of espresso andespresso-type beverages. This channelling directs the liquid throughpreferred pathways in the compressed bed of beverage preparationmaterial preventing uniform exposure of the beverage preparationmaterial to the liquid and resulting in wasted beverage preparationmaterial and a beverage having reduced concentration of dissolved orinfused material. Channelling may occur in particular if the beverageingredient is not uniformly and/or sufficiently compressed in the clampprior to and during water injection.

The present inventors have also found that the bonding of the V-filteredges 172,173 at locations above the outlet channel 157 as shown inFIGS. 3 and 4 results in leakage of liquid through the filter above theoutlet channel, and therefore to incomplete extraction of the coffee,especially of the coffee located near the bottom of the beverageingredient chamber.

It will also be appreciated that, for typical capsules of the abovetypes having a brewing zone of area 25 cm³ to 50 cm³ and at a brewingpressure of about 10 bar gauge or more, a force of the order of 5000Nmay be exerted on the clamp of the beverage preparation apparatus duringbrewing. This requires a clamp having high dimensional stability andstrength under such forces, combined with ease of opening and accessbefore and after brewing. It is also desirable that the clamp shouldprovide optimal compression (tamping) of the coffee bed inside thecapsule before brewing, and further that it should be capable ofsqueezing the pack after brewing to dewater the pack before disposal andto reduce drips.

Accordingly, a need remains for improved capsules, apparatus and methodsfor preparing beverages from capsules, especially at high pressures suchas for producing espresso and espresso-type beverages from flexiblecapsule-type packs.

SUMMARY OF THE INVENTION

In a first aspect, the present invention provides a beverage preparationcapsule containing a beverage preparation ingredient, the beveragecapsule comprising: front and back sheets of substantially air- andliquid-impermeable flexible film materials, the sheets being bondedtogether in face to face relation along a top edge, first and secondside edges, and a bottom edge, wherein a region of the bonding in thebottom edge is releasable by heat and/or pressure to allow escape ofbeverage from the capsule during beverage preparation; the front andback sheets further being bonded together in face to face relation by atransverse seal extending intermediate the top and bottom edges, thetransverse seal being interrupted by a gap, whereby the gap providesfluid communication between a beverage ingredient chamber located abovethe gap and a beverage outlet chamber located below the gap; and afolded filter strip extending transversely across the capsule to providea filter element in the gap, the folded filter strip having a foldextending transversely below the transverse seal and front and back sidepanels extending upwardly through the transverse seal and bonded to thefront and back sheets of the capsule, respectively, wherein the frontand back side panels do not extend more than about 10 mm into thebeverage ingredient chamber above the transverse seal.

Suitably, the folded filter sheet is a simple V-folded filter strip,with the vertex of the V located below the transverse intermediate sealin the capsule, and the side edges of the V extending into, or slightlyabove the transverse seal. However, it is possible that more complexfolded strips such as W-folded strips could be used. It has been foundthat the provision of a V-strip filter that does not extendsignificantly, or at all, above the intermediate transverse seal andtherefore the outlet channel provides improved flow of liquid throughthe ingredient bed in the ingredient chamber during beveragepreparation. Suitably, the front and back side panels of the foldedfilter strip do not extend more than about 5 mm into the beverageingredient chamber above the transverse seal, more suitably they do notso extend by more than about 2 mm. Suitably, the width of the foldedstrip (top to bottom in the capsule) is from about 15 mm to about 25 mm.Thus, for a V-folded strip this corresponds to an unfolded edge-to-edgewidth of from about 30 mm to about 50 mm.

Suitably, the bottom edge of the folded filter strip, e.g. the vertex ofthe V-strip filter, is bonded into the bottom edge seal of the capsule.This has been found to improve opening of the bottom edge seal duringbeverage preparation. Both reliability and cleanliness of opening andthe audible “pop” when the pack opens are surprisingly enhanced by thisfeature.

Suitably, the capsules of the invention further comprise a liquidinjection nozzle having a tubular bore sealed by a freshness barrier,wherein the nozzle is sealed in airtight fashion in the top edge betweenthe front and back sheets.

Suitably, the front and back sheets are bonded together across part ofthe width of the capsule between the intermediate transverse seal andthe bottom seal to define the outlet chamber between the front and backsheets having a width less than the width of the ingredient chamber.

Suitably, the capsule consists essentially of the front and back sheets,the filter strip, optionally the nozzle, and the ingredient. Suitably,the capsule is a single-serve capsule. It may suitably be a disposable,single-use capsule.

Suitably, the gap and outlet chamber are located in an axially centralregion of the capsule, and the outlet chamber has a width of from about20% to about 70% of the width of the beverage ingredient chamber. Thecapsule suitably has substantial mirror symmetry about the longitudinalmedian line.

The gap defining the outlet channel from the beverage ingredient chambersuitably has a width of from about 5 mm to about 25 mm, for example fromabout 8 mm to about 15 mm.

In a second aspect, the present invention provides a beveragepreparation apparatus for preparing a beverage by injection ofpressurized water into a capsule wherein the capsule has at least oneflexible wall, said beverage preparation apparatus including a clampassembly operable between an open configuration and a closed brewingconfiguration for beverage preparation, said clamp assembly comprising:a first clamp member having a recess in an inner wall thereof forreceiving part of a capsule; a second clamp member, said second clampmember comprising a rigid peripheral frame having a central void, and aresilient layer extending across said central void, whereby a frontsurface of said resilient layer defines a second inner wall forreceiving part of a capsule, wherein respective inner walls of saidfirst and second clamp members in said closed brewing configurationdefine a chamber for substantially enclosing and supporting a capsuleduring beverage preparation; and a piston positioned in the central voidof the rigid frame, said piston comprising a piston face for abutting aback surface of said resilient layer and a piston body, wherein saidpiston is resiliently coupled to said rigid peripheral frame to allowlimited resilient movement of said rigid frame relative to said pistonalong a direction of closure of the clamp.

The flexible wall of the capsule is a wall that is deformable by theapparatus and so allow the clamp members of the apparatus to manipulateand rearrange, i.e. compress, the capsule contents.

The direction of closure is defined by the path along which the clampmembers travel when moving from the open configuration to the closedbrewing configuration.

Suitably, the piston is supported on an arm that is pivotingly connectedto a chassis of the apparatus whereby the piston can be swung away fromthe first clamp member about an axis substantially perpendicular to thedirection of closure of the clamp when the clamp is unlocked.

Suitably, the apparatus comprises a drive mechanism coupled to thepiston to drive the second clamp member into the closed position againstthe first clamp member. The drive mechanism may be disengaged from thepiston when the clamp is locked. In these embodiments, the drivemechanism suitably includes a slot in the piston, the slot extendingaway from the piston face in the direction of closure of the clamp, anda drive pin received in the slot, whereby the drive pin can be retractedwithin the slot at the closed and locked position of the clamp todisengage the drive mechanism from the piston.

Suitably, the apparatus comprises a drive mechanism for closing theclamp, the mechanism comprising: a crank arm having a first end coupledto the piston and a second end coupled to a toothed crankshaft, whereinthe crank axle is mounted to the chassis of the apparatus and extendssubstantially perpendicular to the direction of closure of the clamp,and wherein the toothed crankshaft is driven by a toothed drive wheelcoupled to an electric motor.

The inner surface of the resilient region may comprise a concave basesurface for receiving the capsule and one or more pressure padsprojecting from the concave base surface for selectively constrictingone or more regions of a capsule held in the clamp. For example, thepressure pads may comprise or consist of one or more elongate pressurepads extending in a direction generally from an inlet region of theclamp towards an outlet region of the clamp. Suitably, one or more ofthe pressure pads are of a substantially arcuate transverse and/orlongitudinal cross section in the absence of an external force.

The beverage preparation apparatus may comprise a locking mechanism, asdescribed hereinbelow. A locking mechanism may comprise: at least onefirst locking pin projecting from a side of the first clamp element; atleast one second locking pin projecting from a side of the piston; and amovable locking gate having a first flange for abutment against thefirst locking pin in the closed and locked position (when the lockingmechanism is in its closed brewing configuration), and a second flangefor abutment against the second locking pin in the closed and lockedposition, wherein the locking gate is movable when the clamp is closedfrom an unlocked position (open configuration) at which the flanges donot engage the pins to a locked position (closed brewing configuration)in which the flanges engage opposite sides of the first and second pins,respectively, to prevent the first and second pins from moving apartwhile allowing the first and second pins to move towards each other.

Suitably, a plurality of respective pairs of pins are provided onopposite sides of the first clamp member and the piston. This locks theclamp elements together at multiple locations to ensure uniform stresseson the clamp elements and locking elements.

Suitably, the piston comprises a peripheral flange extending behind therigid frame, and the resilient coupling between the piston body and thesecond clamp member comprises a plurality of springs spaced around theperiphery of the rigid frame and the piston flange, whereby relativemovement of the piston towards or away from the rigid frame respectivelycompresses or extends the springs about a zero-displacement relativeposition.

The beverage making apparatus according to the present inventiontypically further comprises: a cup receiving station for locating a cupto receive beverage prepared in the clamp, and a water jet nozzlelocated above the cup receiving station to direct a jet of water into acup in the cup receiving station. In these embodiments the controlsystem and user display are programmed to offer a user a choice betweena homogeneous beverage such as latte and an inhomogeneous beverage suchas cappuccino. If a uniform beverage is selected, then the controlsystem is programmed to inject water into the beverage in the cup afterbeverage preparation in the clamp assembly to swirl and mix the beveragein the cup.

The apparatus may further comprise a capsule recognition device and acontrol system and display programmed to interrupt beverage preparationand to indicate to a user when a capsule of the wrong type has beeninserted in the clamp assembly.

The apparatus of the invention may further comprise a cup receivingstation for locating a cup to receive beverage prepared in the clamp,wherein the cup receiving station comprises a cup detection apparatuscomprising an infrared transmitter and an infrared receiver located suchthat a cup positioned in the receiving station interrupts an infraredbeam between the infrared transmitter and the infrared receiver todetect the presence of a cup in the cup receiving station, wherein theapparatus control and user display are programmed to perform thefollowing steps when the cup detection apparatus does not detect a cupin the cup receiving station: (a) interrupt beverage preparation, and(b) prompt the user to perform one of the following options: either (i)insert a cup into the cup receiving station, or (ii) override the cupdetection function.

The beverage preparation apparatus according to the present invention ispreferably suitable for preparing a beverage from a capsule according tothe present invention. Suitably, the clamp assembly is configured topinch the outlet channel of the capsule when the clamp assembly isclosed and locked around the capsule, and the bottom edge of the capsuleextends outwardly from the clamp to prevent contamination of the clampby the beverage escaping from the capsule.

The apparatus of the invention suitably further comprises an injectortube for injecting water into a capsule held inside the clamp assembly,and a pump for pumping the water through the injector at a pressuregreater than about 5 bar gauge, for example at about 10 bar gauge.

In these embodiments, the beverage preparation apparatus suitablyfurther comprises a second clamp assembly suitable for beveragepreparation from a capsule at pressures less than about 2 bar gauge, asecond injector tube for injecting water into a capsule held inside thesecond clamp assembly, and a pump for pumping the water through thesecond injector tube at a pressure less than about 2 bar gauge, whereinthe apparatus comprises a single control system and user interface tocontrol beverage preparation from both clamp assemblies. The secondclamp etc. may for example be substantially the same as for existinglow-pressure FLAVIA systems. The two clamps in these embodiments aresuitably mounted in a single housing. The apparatus according to theseembodiments offer the user a choice between high-pressure brewedbeverages such as espresso coffee, and low-pressure brewed beveragessuch as filter coffee or tea. Moreover, the low pressure clamp can beused to prepare a milk component of a multi-component beverage from asuitable milk concentrate capsule, optionally with foaming, to which anespresso “shot” can be added from the high pressure clamp.

Thus, the control system and display may be programmed to prompt a userto carry out the following sequential steps in response to a command tobrew a multicomponent beverage:

-   -   (a) insert a first capsule containing a first beverage brewing        ingredient into one of the clamps;    -   (b) wait while a first beverage component is brewed from the        first capsule;    -   (c) transfer a receptacle from a cup receiving station of the        one clamp to a cup receiving station of the other clamp    -   (d) insert a second capsule containing a second beverage brewing        ingredient into the holder of the other clamp; and    -   (e) wait while a second beverage component is brewed from the        second capsule.

Accordingly, in a further aspect the present invention provides abeverage preparation system comprising: a beverage preparation apparatusaccording to the invention having first and second beverage preparationclamps; a plurality of beverage preparation capsules of a first type foruse in a first beverage preparation clamp of the apparatus; and aplurality of beverage preparation capsules of a different type for usein the second beverage preparation clamp of the apparatus.

The capsules according to the present invention may not be ideal for usein low pressure clamps such as conventional FLAVIA clamps. Similarly,conventional FLAVIA capsules such as those shown in FIGS. 1 and 2 maynot be ideal for use in the high pressure brewing clamps of the presentinvention. Therefore, the system according to the invention suitablyincludes apparatus to prevent misuse of capsules of the wrong type inthe respective clamps. This apparatus may be a capsule recognitionsystem as identified above, or one of the following.

For instance, the first clamp incorporates a first key way and thesecond clamp comprises a second key way different from the first keyway, wherein the first key way permits insertion of a first capsule typecomprising a first nozzle configuration through the first clamp key, andthe second key way permits insertion of a second capsule type comprisinga second nozzle configuration through the second clamp key way. Thisprovides a simple mechanical interface to prevent misuse of capsules inthe wrong clamp.

Alternatively, the first clamp incorporates a first nozzle colour sensorand the second clamp comprises a second nozzle colour sensor, andwherein the first capsule type comprises a nozzle having a first colour,and the second capsule type comprises a nozzle having a second colour.

In a further aspect, the present invention provides a method of making abeverage comprising inserting a beverage preparation capsule having abeverage preparation ingredient in a beverage ingredient chamber of thecapsule into the clamp assembly of a beverage preparation apparatusaccording to the invention such that an outlet channel from a beverageingredient chamber of the capsule is pinched between the clamp members;securing the clamp assembly in the closed brewing configuration;injecting water at a pressure of from about 5 to about 15 bar gauge intothe beverage ingredient chamber of said capsule to produce a beverage insaid capsule; and allowing said beverage to escape from the capsule andthe clamp through said outlet channel.

Suitably, the method comprises the steps of: inserting the capsule intothe clamp; securing the first clamp member in a fixed position; followedby moving the second clamp member towards the first clamp member untilthe resilient layer on the rigid frame of the second clamp member abutsagainst a periphery of the first clamp member; followed by furthermoving the piston towards the first clamp member to force the resilientlayer further towards the first clamp member to compress the beverageingredient inside the capsule; followed by said step of injecting saidwater into the beverage ingredient chamber to prepare the beverage;followed by moving the second clamp member away from the first clamp toopen the clamp for removal of the spent capsule.

In a further aspect of the present invention, there is provided abeverage preparation apparatus for preparing a beverage by injection ofwater into a capsule comprising: a first brewing section configured tohold a capsule containing a beverage brewing ingredient, wherein thefirst brewing section comprises a first door that is moveable between aclosed position and an open position for accepting the capsule into thefirst brewing section; a second brewing section configured to hold acapsule containing a beverage brewing ingredient, wherein the secondbrewing section comprises a second door that is moveable between aclosed position and an open position for accepting the capsule into thesecond brewing section; at least one source of hot liquid; at least oneinjector (and preferably wherein an injector is provided for eachbrewing section), wherein an injector is suitable for injecting hotliquid into a capsule held in a brewing section to brew a beveragecomponent in the capsule; and a control system for opening each of thefirst door and second door, wherein the control system is programmed toopen the first door in response to a first command inputted by a userand to open the second door in response to a second command inputted bya user.

DESCRIPTION OF THE DRAWINGS

Further details and specific embodiments of the present invention willnow be described further, by way of example, with reference to theaccompanying drawings, in which:

FIGS. 1, 2 a and 2 b show a FLAVIA® type capsule according to the priorart as hereinbefore described;

FIG. 3 shows a plan view of a prior art beverage preparation capsule asdescribed in WO2012175985;

FIG. 4 shows a longitudinal cross-sectional view of the prior artbeverage preparation capsule of FIG. 3;

FIG. 5 shows a plan view of a beverage preparation capsule according tothe present invention;

FIG. 6 shows a longitudinal cross-sectional view of the beveragepreparation capsule of FIG. 5;

FIG. 7 shows a schematic side elevation view of a clamp assemblycomprising a locking mechanism of a beverage preparation apparatusaccording to the present invention in an open configuration;

FIG. 8 shows a schematic side elevation view of the clamp assemblycomprising a locking mechanism of a beverage preparation of FIG. 7 in aclosed and locked brewing configuration;

FIG. 9 shows a schematic side elevation view of a clamp assembly anddrive mechanism according to the present invention in an openconfiguration;

FIG. 10 shows a schematic side elevation view of the clamp assembly anddrive mechanism of FIG. 9 in the closed brewing configuration;

FIG. 11 shows a schematic side elevation view of a finger guard of thepresent invention in a blocking configuration;

FIG. 12 shows a schematic side elevation view of the finger guard ofFIG. 11 in a non-blocking configuration;

FIG. 13 shows a schematic transverse cross-section through the outletchannel region of a capsule of FIG. 5 when inserted in the clampassembly of the present invention;

FIG. 14 shows a front perspective view of part of a second clamp memberof a beverage preparation apparatus according to the present invention;

FIGS. 15a to 15m show schematic side elevation views partially cut awayof a beverage preparation apparatus according to the invention showingsteps in the preparation of a beverage from a capsule of the invention;

FIG. 16 shows a schematic diagram of a beverage preparation apparatusaccording to the invention;

FIG. 17a shows a side elevation view of a first nozzle for a capsuleaccording to the invention, incorporating a first key profile;

FIG. 17b shows a top plan view of the nozzle of FIG. 17 a;

FIG. 18a shows a side elevation view of a second nozzle for a capsuleaccording to the invention, incorporating a second key profile;

FIG. 18b shows a top plan view of the nozzle of FIG. 18 a;

FIG. 19a shows a transverse cross-section through a first key way in abeverage preparation apparatus according to the present invention forinsertion of a capsule incorporating a nozzle as shown in FIGS. 17a and17b ; and

FIG. 19b shows a transverse cross-section through a second key way in abeverage preparation apparatus according to the present invention forinsertion of a capsule incorporating a nozzle as shown in FIGS. 18a and18 b.

DETAILED DESCRIPTION OF THE INVENTION

In a first aspect, the present invention provides a beverage preparationcapsule containing a beverage preparation ingredient, the beveragecapsule comprising: front and back sheets of substantially air- andliquid-impermeable flexible film materials, the sheets being bondedtogether in face to face relation along a top edge, first and secondside edges, and a bottom edge, wherein a region of the bonding in thebottom edge is releasable by heat and/or pressure to allow escape ofbeverage from the capsule during beverage preparation; the front andback sheets further being bonded together in face to face relation by atransverse seal extending intermediate the top and bottom edges, thetransverse seal being interrupted by a gap, whereby the gap providesfluid communication between a beverage ingredient chamber located abovethe gap and a beverage outlet chamber located below the gap, whereinsaid outlet chamber is in fluid communication with said releasableregion of bonding in the bottom edge; and a V-folded filter strip havingfirst and second edges bonded to internal surfaces of the first andsecond back sheets respectively, said edges extending transverselyacross said capsule within or proximate to the intermediate transverseseal, whereby the V-folded filter strip extends across the gap toprovide a filter element in the gap

The term “capsule” as used herein refers to a suitably sealed containercontaining beverage preparation material, typically particulate materialsuch as ground coffee. The ingredient is sealed inside the capsulebefore use. That is to say, at least the beverage ingredient chamber ofthe capsule is sealed in substantially air- and moisture impermeablefashion. The capsule is suitably formed from materials that aresubstantially impermeable to oxygen and moisture in order to preservethe freshness of the beverage ingredient. Preferably, the capsule issubstantially shelf stable. That is to say, it may be stored at ambienttemperature and atmospheric conditions for a period of at least 3months, preferably at least one year, without significant deteriorationof the contents.

The front and back sheets of the capsule define the capsule body. Theterm “body” is used herein in its usual sense of a three-dimensionalshape including an enclosure for retaining the beverage brewingingredient. It will be appreciated that the capsule body may be of anysuitable shape in plan view, including circular, square, other regularpolygons, or trapezoidal. Suitably, the capsule body is substantiallyrectangular in plan view. Suitable dimensions are: height about 5 cm toabout 12 cm, width about 3 cm to about 8 cm. In these embodiments thewidth of the filter strip is total from about 30 mm to about 50 mm, forexample about 40 mm (i.e. about 20 mm on each side of the fold).

The terms “top” and “bottom” herein, and related expressions such as“above” and “below”, and “front” and “back” are relative expressionsintended to clarify the relative positions of elements of the capsulesand apparatus, with reference to the accompanying drawings. While the“top” end of the capsules may indeed be uppermost in use, it willreadily be appreciated by the skilled person that this may notnecessarily be the case, depending on the orientation of the beveragepreparation machine. In any event, the “top” or “upper” regions of thecapsule are those that are upstream, and “bottom” or “lower” elementsare downstream with respect to the flow of liquid during beveragepreparation. For example, it is possible that the beverage preparationmachine is orientated such that the water flows through the capsule in ahorizontal direction during beverage preparation. In this way the topend of the capsule and the bottom end of the capsule would be at thesame vertical height. It will be appreciated from the description anddrawings of the present invention herein, however, that the beveragepreparation machine is preferably orientated such that the water flowsthrough the capsule in a substantially vertical direction duringbeverage preparation.

The front and back flexible sheets are bonded together to define aningredient chamber in which the beverage preparation ingredient isstored, and in which the beverage is prepared by infusion or dissolutionof the beverage preparation ingredient. The ingredient chamber issuitably substantially filled by the ingredient, for example at leastabout 50% of the volume of the chamber is filled by the ingredient. Theuncompressed volume of the chamber is suitably from about 5 ml to about100 ml.

The gap in the intermediate transverse seal defines an outlet channelextending from the beverage ingredient chamber, through which thebeverage escapes from the chamber during beverage preparation. Theoutlet channel is substantially free of beverage ingredient. The outletchannel has a length in the direction of flow of the beverage, and across-section perpendicular to that flow. The length of the outletchannel is suitably from about 1 mm to about 20 mm, for example about 5mm to about 10 mm. The width of the outlet channel is suitably fromabout 5 mm to about 50 mm, suitably from about 10 mm to about 30 mm, forexample about 15 mm. The uncompressed mean cross-section area of theoutlet channel is substantially less than that of the beverageingredient chamber, for example the mean uncompressed cross-sectionalarea of the outlet channel is suitably no more than about 10% of themean uncompressed cross-sectional area of the beverage ingredientchamber. Furthermore, as will be explained further below, the outletchannel is normally compressed (pinched) during beverage preparation tofurther reduce its cross-section. In embodiments, the mean width of theoutlet channel is suitably from about 5 mm to about 30 mm, for exampleabout 10 mm to about 20 mm, and the mean uncompressed depth of theoutlet channel is less than about 4 mm, for example from about 0.4 mm toabout 2 mm.

The V-filter strip is a simple folded strip of filter material, suitablya nonwoven textile material, for example a nonwoven web of polypropylenefibers. The total width of the strip (measured from the firstlongitudinal edge to the opposite longitudinal edge, perpendicular tothe V-fold) is suitably from about 30 mm to about 50 mm, for exampleabout 35 mm to about 45 mm. The V-fold is suitably located on the medianline of the strip. The strip is suitably of substantially the samelength as the width as the capsule, whereby it is bonded transverselyinto the capsule across substantially the whole width of the capsule,suitably with the short end edges of the strip embedded in the side edgeseals of the capsule. The strip has two longitudinal edges remote fromthe V-fold. Each of these edges is bonded to the front and backsidewalls of the capsules, respectively, transversely to the axis of thecapsule, such that the V-fold is located below the side edges. It is afeature of this invention that the side edges of the V-strip are bondedto the side walls within or proximate to the intermediate transverseseal, whereby the edges of the V-strip do not extend above thetransverse seal to any appreciable extent. That is to say, the edges donot project above the top of the transverse seal (and therefore abovethe top of the outlet channel) by more than about 10 mm, preferably notby more than about 5 mm, more preferably they do not so extend at all.This feature helps to ensure that the ingredient bed is fully and evenlywetted and extracted by the flow of liquid through the ingredientchamber. The present inventors have found that the prior art capsules ofFIGS. 3 and 4 that have the V-strip filter bonded to the side walls wellabove the transverse intermediate seal allow liquid to escape sidewaysthrough the filter above the outlet channel and to flow downwardsintermediate the filter and the side wall of the ingredient chamberwithout fully extracting the ingredient. The present invention overcomesthis problem.

The filter strip is bonded to the front and back sheets in theintermediate transverse seal by heat or ultrasonic bonding, simultaneouswith forming the intermediate transverse seal. Accordingly, the filterstrip suitably contains thermoplastic fibers to assist such bonding.

The basis of operation of the capsules according to the invention isthat the beverage is prepared by injection of water into the beverageingredient chamber where the beverage is formed, and the beverage isfiltered as it escapes from the ingredient chamber through the outletchannel. The beverage cannot escape from the body without passingthrough the filter. The filtration material generates a back pressureacross the outlet channel, whereby high brewing pressures can bemaintained inside the ingredient chamber (e.g. for brewing espressocoffee) without excessively fast escape of beverage. This back pressurecan be regulated or fixed by applying a pinch to the outlet channel tocompress the filtration material, thereby varying the liquid escapecross-section through the outlet channel. The filtration material issufficiently compressible, and preferably resilient, to enable controlof the liquid escape cross-section by compressing the filtrationmaterial.

The sheet or flexible film material used to form the body of the capsulewill usually be a laminate comprising two or more of the followinglayers: a thermoplastic sealant layer for bonding the sheet to othermembers of the package; a substantially gas-impermeable barrier layer,which suitably is a metal film such as aluminium film; adhesion layersto improve adhesion between other layers of the laminate; structurallayers, for example to provide puncture resistance; and/or a printingsubstrate layer. The structural layers could be made of polyolefins,polyester, nylons, or other polymers as is well known in the art. Incertain embodiments, the front and back of the capsule comprise flexiblesheets. In certain embodiments, the front and back faces could be formedfrom a single sheet of material folded over along one edge. In certainembodiments, at least a region of at least one of the front and backsheets may be transparent to allow the user to see the ingredient.

The front and back sheets and/or the filter and/or the injection nozzlemay comprise or consist essentially of a compostable material. The term“compostable” signifies that the material is substantially broken downwithin a few months, suitably within a few weeks, when it is composted.Typically, the capsule is at least about 90% composted within sixmonths, as determined by the method of ISO14855, as in EN13432.Thermoplastic compostable polymers that could be used for the capsuleinclude polymers and copolymers of lactic acid and glycolic acid,polyhydroxybutyrates, polyvinyl alcohols (PVOH), ethylene vinyl alcohols(EVOH), starch derivatives, cellulose and cellulose derivatives, andmixtures thereof.

Suitable materials and methods of manufacture are described, forexample, in the already-cited patent specifications relating to theFLAVIA capsule system, for example GB-A-2121762, GB-A-2122881,EP-A-0179641, EP-A-0247841 and WO-A-9905044.

The capsule further comprises a downstream (outlet) chamber located influid communication with the downstream end of the outlet channelopposite the beverage ingredient chamber. Suitably, the beverageingredient chamber, the outlet channel, and the downstream chamber areall formed by bonding together the front and back faces of sheetmaterial with a suitable pattern (profile) of bonding. The downstreamchamber is suitably considerably smaller than the beverage ingredientchamber, for example no more than about 25% of the volume of thebeverage ingredient chamber. The outlet channel and the downstreamchamber (where present) are suitably located at an end of the capsuleopposite to the locus of liquid injection, e.g. the injection nozzle ofthe capsule. In embodiments, the capsule is suitably substantiallyaxially symmetric (i.e. has two-fold rotation/reflection symmetry abouta longitudinal axis), and suitably the injection nozzle (where present),the outlet channel, and the downstream chamber (where present) lie onthe longitudinal axis.

The downstream chamber being wider than the outlet channel and in fluidcommunication with the releasable bottom seal on the capsule assistsopening of this seal when the downstream chamber fills with hot beveragefrom the channel.

The downstream chamber may also function as a conditioning chamber forthe beverage exiting the outlet, that is to say a chamber in whichbubbles within the liquid can separate from the liquid to form a “crema”on espresso coffee. Alternatively or additionally the downstream chambermay comprise one or more conduits for directing the beverage to one ormore beverage outlets. For example, the downstream chamber may bebifurcated to direct the beverage to two outlets located adjacent toopposite edges of the capsule. In other embodiments, the downstreamchamber may be funnel-shaped to direct the beverage to a single outletlocated centrally.

As already noted, the beverage outlet from the downstream chamber issealed with a releasable seal that is opened under the influence of heatand/or pressure of beverage in the downstream chamber (optionallyassisted by external heating such as hot air applied externally by thebrewing apparatus). The releasable seal is substantially impermeable toair or moisture so as to preserve the freshness of the beverage brewingingredient by preventing ingress of air or moisture through the liquidguide before brewing commences. For example, the releasable seal maycomprise a layer of pressure-sensitive adhesive as described inEP-A-0179641 or WO99/05036.

In preferred embodiments, the bottom of the V-strip filter (i.e. thevertex of the V) is bonded inside the bottom edge seal of the capsule,in particular within the releasable seal portion. It has been found thatembedding the bottom of the V-strip filter within the releasable sealresults in more reliable opening of the pack and a more marked “pop”sound when the pack opens.

Suitably, the capsule further comprises a nozzle through which liquidcan be injected into the chamber containing the beverage preparationingredient. The nozzle is suitably a thermoplastic nozzle having atubular bore for receiving a liquid injector tube from a beveragepreparation machine. The bore may be cylindrical, or it may have anon-circular cross-section. The nozzle may have a single outlet insidethe chamber, or it may have a plurality of outlets inside the chamber,for example an outlet manifold for distributing the beverage makingliquid within the beverage ingredient enclosure. The nozzle outlet oroutlets may be located at an edge of the capsule, or they may be locatedmore centrally within the enclosure. Suitable nozzles are described inEP-A-0179641 and WO-A-9905036. The inlet end of the nozzle may comprisean annular seat (recess) around the bore for receiving an O-ring on theinjection tube to form a pressure-tight seal between the injection tubeand the nozzle.

The nozzle suitably comprises a flange at its inlet end to assistgripping of the nozzle bore by the brewer clamp. The flange may beprofiled in longitudinal cross-section to define a key profile, wherebythe capsule can only be inserted into the brewer clamp if the keyprofile of the nozzle flange fits a key way in the brewer clamp.Alternatively or additionally, the nozzle may be molded from a colouredplastic, for example a black, white, red or blue plastic, to assistcapsule recognition by the user and/or by optical capsule recognitiondevices on the brewer. This can be used to ensure that inappropriatecapsules are not accidentally inserted into the brewer.

Suitably, the nozzle is sealed by a frangible barrier to maintainfreshness of the beverage preparation ingredient prior to preparation ofthe beverage. The frangible barrier may comprise, or consist essentiallyof, a thin sheet of film material that can be pierced by a liquidinjector tube on a beverage making machine. In other embodiments inwhich the nozzle is molded from thermoplastics, the frangible barriermay be a thermoplastic barrier molded in one piece with the nozzle, andhaving at least a peripheral region of weakness to enable the barrier tobe pierced by a liquid injector tube on a beverage making machine.

Typically, the capsule is a single-serve capsule. That is to say, theamount of ingredient contained in the capsules is sufficient for thepreparation of one portion of beverage, i.e. in the case of espressocoffee from about 10 to about 250 ml, suitably from about 25 ml to about125 ml of beverage. For example, the capsule may contain from about 2 gto about 25 g of ground coffee or from about 1 g to about 9 g of leaftea. Suitably, the capsule is a single-use capsule that is disposed of,or recycled, after one use.

In use, as explained further below, the capsule is substantiallycompletely enclosed by, and in contact with, the inner surfaces of theclamp cavity. The cavity supports the beverage brewing capsule enclosedwithin the cavity, thereby enabling high hydrostatic pressures to bedeveloped inside the capsule without bursting the capsule. Indeed, it isenvisaged that the capsule could be formed with very thin walls, therebyreducing the amount of plastic waste material that remains afterbrewing.

It can readily be seen that the above capsules can be manufactured usingonly minor modification of the methods used to make the capsules ofGB-A-2121762, GB-A-2122881, EP-A-0179641, EP-A-0247841 and WO-A-9905044.In particular, the capsules can be manufactured from continuous stripsof front and back sheet material and a continuous strip of V-foldedfilter material, using suitably profiled heat or ultrasonic sealing jawsto form the top, edge, and intermediate seals and the region of bondingbelow the intermediate seal that defines the outlet chamber.

In a second aspect, the invention provides a beverage preparationapparatus for preparing a beverage by injection of pressurized waterinto a capsule wherein the capsule has at least one flexible wall, thebeverage preparation apparatus including a clamp assembly operablebetween an open configuration and a closed brewing configuration forbeverage preparation, the clamp assembly comprising: a first clampmember having a recess in an inner wall thereof for receiving part of acapsule; a second clamp member the second clamp member comprising arigid peripheral frame and a resilient central region formed by aresilient layer spanning the peripheral frame, wherein respective innerwalls of the first and second clamp members in the closed brewingconfiguration define a chamber for substantially enclosing andsupporting a capsule during beverage preparation, the chamber having aninlet region for injection of water and an outlet region for escape of abeverage; a piston member comprising a piston face abutting theresilient central region of the second clamp member, and a piston bodyresiliently coupled to the rigid peripheral frame to allow limitedresilient movement of the piston member relative to the rigid peripheralframe; and a drive element acting on the piston to open and close theclamp assembly.

Suitably, the beverage preparation apparatus according to the presentinvention is suitable for preparing a beverage from a capsule accordingto the invention. The beverage preparation apparatus suitably comprisesa rigid chassis of metal or similar strong material to which the movingparts are anchored, together with a housing to surround the chassis andthe moving parts.

Suitably, the first and second clamp members are movable together inface-to-face fashion along a path (hereinafter “the direction ofclosure”) to grip and enclose the capsule. Suitably, one of the firstand second clamp members is fixed relative to the chassis of thebeverage preparation apparatus following insertion of the capsule andprior to clamping. The fixed clamp element is suitably the first clampmember. The other clamp member is moved by a drive mechanism along apath to clamp the capsule. Suitably, at least a final part of said pathis substantially linear along said direction of closure.

An inlet region of the chamber formed by the first and second clampmembers is normally located at a first end of the chamber (also referredto herein as the “upper end”) and the outlet region is normally locatedat the opposite end (also referred to herein as the “lower end”). Inembodiments such as those described in detail herein, the inlet issuitably located above the outlet, for example substantially directlyabove the outlet. The term “longitudinal” refers to the direction fromthe inlet end to the outlet end. The term “transverse” or “horizontal”herein refers to a direction perpendicular to the longitudinal. The term“median line” herein refers to the transverse line located half-waybetween the inlet and the outlet. The term “region proximate to theinlet” refers to the region of the clamp chamber located between themedian line and the inlet. The term “region proximate to the outlet”refers to the region of the clamp chamber located between the medianline and the outlet.

The inner surfaces of the clamp members define a chamber for thebeverage preparation capsule when the clamp assembly is in a closedposition. The beverage preparation capsule is supported by and normallysubstantially completely enclosed by and in contact with the clampmembers, thereby enabling high hydrostatic pressures to be developedinside the capsule without bursting the capsule. Indeed, it is envisagedthat the capsule could be formed with very thin walls, thereby reducingthe amount of plastic waste material that remains after use. Thesubstantial enclosure formed by the first clamp member and the secondclamp member in the closed brewing configuration will have an inletopening to allow liquid to be injected into the capsule that will beheld within the chamber and it also has an outlet for allowing thebrewed beverage to leave the chamber. Apart from this inlet and outlet,the first clamp member and the second clamp member form an enclosedchamber when in the closed brewing configuration.

The first clamp member suitably encloses and supports one of the frontor back faces of the capsule in use. Suitably, an internal surface ofthe clamp member is profiled to fit around said front or back face ofthe capsule, e.g. said internal surface is concave. The first clampmember is pivotally connected to the chassis of the beverage preparationapparatus. In a preferred embodiment, the first clamp member is mountedvertically (i.e. the first clamp member has its inlet at the upper endand its outlet at the lower end), and the first clamp member is locatedoutwardly from the second clamp member within the apparatus. In apreferred embodiment, the first clamp member is able to pivot about oneedge relative to the chassis, preferably the lower (outlet end) edge forinsertion of a capsule into the first clamp member. In this way thefirst clamp member functions as a door that can be opened for insertionof a capsule and closed when the apparatus is in operation or at rest.

The first clamp member may be locked into its closed brewingconfiguration by a securing mechanism. Each of the clamp members may beindependently placed in their closed brewing configuration. It is onlywhen both clamping members are placed in their closed brewingconfigurations that the clamping chamber between the two members isestablished.

The securing mechanism of the first clamp member can be unlocked toallow the first clamp member to be accessed, such as to insert a capsulefor beverage preparation. The securing mechanism can secure the firstclamp member to the chassis of the apparatus. Accordingly the securingmechanism comprises complementary securing components on part of thefirst clamping member and the second part on the chassis. In this way,the first clamp member is resistant to being displaced from its closedbrewing configuration when a force is applied to it during the brewingprocess. The securing mechanism may be a latch. The latch may have aspring loaded arm pivotally connected to the first clamp member and acomplementary protrusion extending from the chassis which the springloaded arm slides over when the first clamp member is moved to itsclosed brewing configuration, the arm resiliently hooking around theprotrusion when the first clamp member reaches its closed brewingconfiguration. In this way the first clamp member can be easily movedfrom its open configuration to its closed brewing configuration butcannot return without the spring loaded arm being moved pivotally out ofengagement with the chassis protrusion.

In these embodiments where the first clamp member can be pivoted forcapsule insertion, the first clamp member may be biased with a spring orequivalent means so that it pivots to the open position when the lockingmechanism is unlatched. Alternatively, a motor may be operativelyassociated with the first clamp member to pivot the first clamp memberbetween open and closed positions. The first clamp member may made ofmetal or similar rigid material, and it may be lined with a layer ofresilient material.

The first clamp member may comprise a removable cover that forms theinner wall of the first clamp member. The removable cover may be held inposition by an interference fit, latches or an arrangement of magnets.The presence of a removable cover enables easy cleaning of thecapsule-facing surface of the first clamp member by removing theremovable cover from the apparatus.

The second clamp member comprises a resilient layer (made from anysuitable material, such as an elastomeric material) supported on a rigidframe having a central void. The resilient layer has a front surface forcontacting and enclosing the beverage capsule, and a back surface. Theresilient layer extends across the void in the central region of therigid frame. The resilient layer is such that it may elastically deformunder application of a force (in particular a force applied by thepiston as described below). The rigid frame is not deformable in thebeverage preparation apparatus under the forces experienced during theoperation thereof.

The piston extends inside the void of the rigid frame and has a pistonface that abuts against the back of the resilient layer, wherebydisplacement of the piston towards the rigid frame in the closuredirection of the second clamp member (as defined above) causes thepiston face to press against the back of the resilient layer and todisplace the resilient layer into the beverage preparation cavity of theclamp. In this way the clamp assembly can tamp, i.e. compress, thecapsule in the clamp chamber. This also supports the contents of thecapsule during injection of liquid enabling the attainment of highbrewing pressures.

The piston is coupled to the rigid frame by resilient means, such as aspring. A plurality of springs may be spaced around the periphery of thepiston and the rigid frame to act as the resilient means. The presenceof resilient means permits resilient displacement of the piston for alimited distance towards or away from the rigid frame about a central(zero displacement) position. The central position is the rest positionof the piston relative to the rigid frame when no force is acting toimpart a relative movement between the two components. In the centralposition, the piston face is located just abutting, or a short distancesuch as 0-10 mm, behind the back of the resilient layer. The resilientmeans permit the piston to be displaced for a limited distance, forexample 5-15 mm towards the rigid frame to displace the resilient layerforward from the frame in the direction of closure of the second clampmember. In this manner the piston can move beyond the central position,while the rigid frame maintains contact with the first clamp member,ensuring the capsule in the clamp chamber remains substantially enclosedand allowing the capsule to remain gripped between the rigid frame andthe first clamp member even though the piston is moving. Once a maximumdisplacement of the piston in the frame has been reached in thisdirection, the piston may abut in non-resilient fashion against theframe so that any further displacement of the piston would requiredisplacement of the frame, which is resisted by the locking of the firstclamp member to the chassis when the clamp assembly is in the closedbrewing configuration.

As described hereinabove, the resilient coupling between the rigid frameand the piston allows the movement of the piston to move the rigid frameinto contact with the first clamp member and then ensure uniform contactall around the periphery of the first clamp member. The movement of thepiston may continue relative to the rigid frame so as to tamp thecontents of the capsule present between the two clamp members. In thisway, the resilient means increases the tolerances to which the clampassembly is manufactured and/or operated, since the resilient meansallows compensation if one part of the rigid frame contacts the firstclamp member before the rest of the rigid frame, and ensures uniformcontact between the first and second clamp members.

As described hereinabove, the resilient means may be in the form ofsprings. The springs may be present around bolts that extend between therigid frame and the piston. The bolts can extend from one of the pistonor the rigid frame and be received in the other component (i.e. therigid frame or piston, as appropriate) so as to ensure the pistonremains aligned with the void in the centre of the rigid frame and thatthe springs remain in place between the piston and the rigid frame.

The rigid frame is suitably made of metal or rigid plastic. It suitablyhas dimensions similar to the outer dimensions of the beveragepreparation chamber of the capsule to be brewed, whereby the edges ofthe beverage preparation chamber are tightly gripped between the rigidframe (including any resilient layer over the frame) and opposed edgesof the first clamp member during beverage preparation to provide apressure-tight seal around the beverage preparation chamber.

The resilient layer is suitably of similar size to the rigid frame andis suitably provided with a peripheral flange, whereby it is fitted overthe front face of the rigid frame with the flange forming aninterference fit or snap fit around the outer periphery of the rigidframe to retain the resilient layer on the frame. This allows theresilient layer to be replaced easily when it becomes worn.

The resilient material of the resilient layer is conformable butsuitably substantially incompressible, for example it may be a solidlayer of elastomer. Typically, the layer of elastomer is from 5 to 25 mmthick and has Shore hardness of from 10 to 60 Shore, preferably from 20to 50 Shore. The resilience of the front surface of the resilient layermay differ in different regions of the layer so as to allow the shape ofthe cavity to change in response to pressure during brewing. The frontsurface may also be profiled with pressure pads to improve liquid flowthrough the capsule during brewing, as described further below.

It has been found that improved beverage preparation can be achievedwhen the inner surface of one or more of the clamp members comprises oneor more pressure pads that protrude into the chamber formed by the clampassembly when in a closed position. The pressure pads assure uniformcompression of the beverage ingredient bed inside the capsule. Thepressure pads may be configured or profiled to optimize the flow ofliquid through the beverage ingredient bed. Suitably, the pressure padsare provided on the front surface of the resilient layer.

When the clamp assembly is in a closed brewing configuration andenclosing the beverage preparation capsule in the chamber, the one ormore pressure pads squeeze an upper part of the enclosed capsule priorto injection of water into the beverage preparation capsule. This inturn helps to hold and compress the bed of beverage preparation material(such as coffee) within the capsule, which allows the beveragepreparation medium (typically water) to flow uniformly through the bed,thus minimising channelling of liquid through the beverage preparationmaterial during brewing and improving extraction of the beveragepreparation material into the beverage preparation medium.

The resilient layer may deform and adjust to compensate for theirregular form of beverage preparation capsules and/or different amountsof ingredient inside the capsules, and may also compensate forvariations in pressure during fluid injection thus regulating thehydrostatic pressure within the capsule. This results in a more uniformexposure of the compressed bed of beverage preparation material to theliquid medium (typically water) which improves diffusion. This providesa beverage of increased quality whilst simultaneously reducing waste ofbeverage preparation material due to channelling.

Furthermore, this deformability allows the pressure pads to adapt tobeverage preparation capsules containing different amounts ofingredients, improving the versatility of the clamp assembly.

Suitably, in the above embodiments, a concave base front surface of theelastomeric layer of the second clamp element is profiled to conformgenerally to the shape of the capsule. This enables the inner surface ofthe clamp to conform to the outer surface of the beverage preparationcapsule and thereby prevent the capsule from bursting when pressurizedliquid is injected into the capsule. The accurate conformity of theclamp surface to the outer surface of the capsule in use also assistsbeverage brewing quality by reducing the channelling of liquid throughthe bed of beverage brewing ingredient, since it promotes uniformcompression of the beverage brewing ingredient.

The pressure pads projecting from the inner surface of the clamp membermay be configured to compress the beverage ingredient and to minimisethe volume of air or liquid in the beverage preparation capsule duringbrewing. This advantageously minimises the volume of liquid in thecapsule thus assisting in the preparation of more concentratedbeverages, such as espresso, by maximising exposure of liquid to the bedand providing a more efficient process of beverage preparation.

The pressure pad(s) protruding from the inner surface of the resilientlayer of the second clamp member into the chamber formed by the clampmembers in a closed brewing configuration may be of any suitableconfiguration to achieve the desired object of squeezing out the headspace of the capsule and compressing the coffee bed inside the capsule.Typically, one or more of said pressure pads are of a substantiallyarcuate transverse and/or longitudinal cross section in the absence ofan external force. The pressure pads suitably have a rounded (biconvex),cushion-like shape. The arcuate pressure pads suitably intersect saidconcave base surface at a contact angle of from about 2° to about 45°,for example from about 10° to about 30°. The arcuate pressure padssuitably have a maximum height (measured from the tangent to theunderlying curve of the base surface) of from about 1 mm to about 15 mm,for example from about 4 mm to about 10 mm.

The pressure pads are suitably located principally proximate to theinlet region of the clamp enclosure. That is to say, more than half ofthe pressure pad volume is located in the upper half of the clampchamber. This positioning achieves the objective of squeezing out headspace from the capsule and compressing the ingredient bed into thebottom of the capsule. This positioning also allows the profile of thepressure pads to guide the flow of water into the ingredient bed.

While squeezing the upper part of the capsule, it remains necessary forthe pressure pads to allow passage of liquid to the ingredient bed inthe lower part of the capsule. For this reason the pressure pad(s) aresuitably profiled in transverse cross-section to define one or morelongitudinal channels of lesser height. The liquid can flow through thecapsule underneath these channels. Suitably, at least one of thechannels is located substantially centrally so as to direct flowcentrally onto the ingredient bed. For example, the pressure pad(s) mayhave a generally m-shaped transverse cross-section.

The one or more pressure pads are preferably elongate in shape andextend generally in a direction from the inlet region towards the outletregion. The or each pressure pad may independently extend from about 20%to about 80% of the length of the chamber, for example, from about 30%to about 75% of the length of the chamber. In other words, while thepressure pad(s) are located primarily proximate to the inlet region,they may extend beyond the median line of the cavity towards the outletregion.

In some embodiments, only one pressure pad is present in the clampassembly. In other embodiments, a clamp member comprising pressure padsmay comprise more than one pressure pad. In some embodiments, from 1 to10 pressure pads may be present. In a preferred embodiment, from 1 to 4pressure pads may be present, for example, a clamp member may comprisethree pressure pads.

Suitably, the pressure pads consist of three pillow-like (biconvex)elongate pads extending from the inlet towards the outlet on theresilient layer of the second clamp member. The pads suitably overlaptransversely so as to present a corrugated inner surface. Suitably, theouter pads are of higher profile than the central elongate pad.Suitably, the pads do not extend all the way to the outlet, therebyleaving a space in the outlet region of the clamp cavity into which thebeverage ingredient is compressed.

As previously noted, the water pressure inside the clamp can exertforces of 5000 N or more on the clamp members during brewing. This forcemust be safely contained. Moreover, this force acting on the clamp drivemechanism of the apparatus may force the drive mechanism out of thecorrect alignment. Therefore, the beverage brewing apparatus of thepresent invention is suitably configured so that this level of force isnot transferred in such a way that it causes damage to the drivemechanism.

A preferred method to achieve this is to utilise a, so-called,top-dead-centre (TDC) arrangement in order to geometrically lock thesecond clamp member into position. In this approach, the drive mechanismcomprises a crankshaft and a crank arm, such that the crankshaft rotatesabout a crankshaft centre and is connected to a first end of the crankarm at a first pivot point, so that crank arm can pivot relative to thecrankshaft. The second end of the crank arm, opposite the first end, isconnected to the piston at a second pivot point. This allows the crankarm to pivot relative to the piston. The piston's movement isconstrained to move towards and away from the first clamp member,typically in a linear manner. Thus, as the crankshaft is driven inrotation by a motor, the piston face is either moved towards or awayfrom the first clamp member. At the top-dead-centre arrangement, thepiston face is at its furthest possible position from the crankshaftcentre and the crankshaft centre, first pivot point and the second pivotpoint are aligned, such that the first pivot point is positioned betweenthe crankshaft centre and the second pivot point. Also, any forceexerted on the crank arm and crank shaft from the second clamp member,via the piston, is in the direction of alignment of the pivot points. Inthis position, any force exerted on the piston face does not result inrotation of the crankshaft and so eliminates the risk of back-drivingthe motor and thereby protects it from potential damage. Thus, in thetop-dead-centre position, the movable parts (piston and crankshaft) aregeometrically locked such that the second clamp member is held inposition against the high brewing forces that occur in the clampchamber.

There is an acceptable degree of tolerance associated with thetop-dead-centre arrangement since the motor can provide some resistanceto back-driving forces without being damaged. In the present invention,the top-dead-centre arrangement remains effective provided that thecrankshaft centre, the first pivot point and the second pivot point aresubstantially aligned and substantially in the top-dead-centrearrangement. In this context, the term “substantially” means that thecrankshaft may be at an angle which is no more than ±5°, preferably nomore than ±2.4° away from the top-dead-centre arrangement.

The top-dead-centre arrangement described hereinabove means that thesecond clamp member is locked in position without the need for complexadditional components, such as the locking mechanism shown in FIGS. 7and 8.

As an alternative to locking the second clamp position into position viaa top-dead-centre arrangement (or possibly even additionally thereto),the apparatus of present invention may comprise a locking mechanismwhich locks the first clamp member and the second clamp member in theclosed brewing configuration. One such locking mechanism is shown inFIGS. 7 and 8. The locking mechanism may allow limited deformation ofthe second clamp member's resilient layer in the closed brewingconfiguration to achieve compaction (tamping) of the capsule beforebrewing, and/or dewatering of the capsule after brewing. Suitably, thelocking mechanism engages the first clamp member and the piston, butdoes not directly engage the rigid frame or the resilient layer.Instead, in the closed brewing configuration the rigid frame of thesecond clamp member is forced against the first clamp member to seal thecapsule enclosure, forming the clamp chamber, by resilient forcetransmitted from the piston to the rigid frame by the resilient couplingbetween the piston and the rigid frame. The resilient coupling and thelocking mechanism allow further limited movement of the piston towardsthe resilient frame at the closed brewing configuration, for example toassist unlatching of the locking mechanism and/or to push the resilientlayer further into the brewing cavity to compact the beverage ingredientinside the capsule and/or to dewater the capsule after beveragepreparation. Finally, the apparatus is suitably configured to uncouplethe drive mechanism from the piston while brewing is taking place sothat the whole of the force exerted by the brewing pressure inside theclamp chamber is taken by the locking mechanism and not by the drivemechanism.

Suitably, the locking mechanism comprises: at least one first lockingpin projecting from a side of the first clamp member; at least onesecond locking pin projecting from a side of the piston; and a movablelocking gate having a first flange for abutment against the firstlocking pin in the closed and locked position (which is also referred toherein as the locking mechanism's closed brewing configuration), and asecond flange for abutment against the second locking pin in the closedand locked position, wherein the locking gate is movable when the clampassembly is in the closed brewing configuration from an open position atwhich the flanges do not engage the pins to a locked position in whichthe flanges engage opposite sides of the first and second pins,respectively, to prevent the first and second pins from moving apartwhile allowing the first and second pins to move towards each other.

Suitably, the pins on the first clamp member and on the piston arelocated opposite each other on a line substantially parallel to thedirection of closure of the clamp members. Suitably, respective firstand second locking pins and locking gates are located on opposite sidesof the first clamp member and the piston. Suitably, two, three or morepairs of locking pins are provided at spaced locations on respectivesides of the first clamp member and the piston, with corresponding gatebars and locking flanges to provide locking on both sides at multiplespaced locations.

The locking gate suitably comprises a vertical drive shaft and one ormore transverse locking bars attached to the drive shaft and having therespective flanges at opposite ends of each locking bar. “Transverse”here means in the direction of closure of the clamp members. The lockinggate is suitably linked to the chassis of the apparatus and is movedperpendicular to the direction of closure of the clamp halves by asuitable drive mechanism.

One or both of the clamp members may include a heater to heat thebeverage ingredient inside the capsule before and/or during beveragepreparation. The heater may, for example, comprise an electric heaterelement inside or on the surface of one or both of the clamp members. Inother embodiments, one or both of the clamp members may be heated bycirculation of hot water or steam through conduits inside the member.The heater suitably achieves a temperature of 90-110° C. at the surfaceof the heated clamp member. The heating of the beverage ingredient isdesirable in order to provide a constant, optimised extractiontemperature, for example about 90° C. to 95° C. for espresso coffee. Inthe absence of external heating the thermal energy needed to heat up thebeverage ingredient can cause an initial drop in the brewing temperaturebelow optimum values, especially for drinks that require a low-volume ofhot water, such as espresso coffee.

The maximum volume of the brewing chamber when the clamp is in theclosed and locked position in the absence of internal pressure issuitably from about 25 cm³ to about 250 cm³, more suitably from about 30cm³ to about 150 cm³. The minimum volume when the piston is fullyextended into the brewing chamber is suitably about 75% or less of themaximum volume, for example about 50% or less of the maximum volume.

The clamp assembly is adapted to apply a pinch force to the outletchannel from the beverage ingredient chamber of the capsule so as toachieve an optimum combination of beverage escape rate from the capsuleand back pressure inside the beverage ingredient chamber to optimizebeverage quality and brewing speed. For example, the clamping apparatusin an outlet region from the brewing chamber may comprise clamp elementsconfigured to pinch the outlet channel of the capsule to provide theconstriction. Various arrangements are suitable, including (a) afixed-configuration outlet constriction, (b) an adjustable constriction,and/or (c) a biased constriction.

In the simplest arrangement, the clamp assembly in the closed positionhas internal surfaces in the outlet channel region that define anopening of fixed size and shape that provides the desired degree ofcompression to the outlet channel of the capsule. For example, one clampmember may have a flat surface in this region and the other clamp membermay have a flat surface with a channel of the desired dimensions cutinto the surface thereof. When the flat surfaces are brought intoabutment when the clamp assembly is closed, the desired opening in thebottom of the clamp is formed by said channel. Suitably, for example foruse with capsules of the kind shown in FIGS. 5 and 6, the fixed gapprovided in the bottom of the clamp chamber has a depth of from about0.1 mm to about 0.8 mm, and a width of from about 10 mm to about 20 mm,for example about 15 mm. This provides the desired pinch force on theoutlet channel of the capsule. Suitably, the channel is provided in arigid surface of the first clamp member and the flat surface is providedby the layer of elastomer over the rigid frame of the second clampmember.

In other embodiments, the size of the opening formed at the outletregion of the clamp where the pinch force is applied to the capsule canbe adjusted, for example by mounting the appropriate portion of one ofthe clamp members on a screw. This allows the size of the opening to beoptimized for different capsule sizes, ingredients and/or desiredback-pressure in the capsule. Indeed, by increasing the size of theopening sufficiently, this allows the clamp to be used both forhigh-pressure (e.g. espresso) brewing, but also for low-pressure (e.g.filter coffee or tea) brewing. The opening is constricted forhigh-pressure brewing so as to maintain a high back pressure in theingredient chamber. The opening is widened for low-pressure brewing soas to allow a satisfactory flow rate through the outlet channel whilekeeping the back pressure in the brewing chamber below about 1.5 bar.

In yet other embodiments, at least one of the members providing saidpinch has an inner surface in said fluid exit region that is biased toapply a pinch force to a capsule in the chamber. The biasing meanscompensates for variations in pack shape, and also compensates fordeformation of the clamp members as the capsule is pressurized byinjected water. Suitably, the said inner surface in the fluid exitregion may be biased by being supported on a spring as described in moredetail in WO2012175985. The biasing means may be adjustable to vary thebias force.

The second clamp member may be supported by an arm fixed to the pistonand extending substantially perpendicular to the direction of closure ofthe clamp. The end of the arm distal to the piston is attached to thechassis of the beverage preparation apparatus by a pivoting connection.This allows the arm to swing the second clamp member away from the firstclamp member to open the clamp and allow disposal of the capsule into abin inside the apparatus. The piston may be moved by a drive pinreceived in the slot in the back of the piston. The drive pin issuitably attached to one end of a crank arm. The other end of the crankarm may be attached by a pivoting connection to a toothed crankshaftthat is driven by an electric motor having a toothed wheel engaging thetoothed crankshaft with suitable gearing to provide a further mechanicaladvantage. The crankshaft rotates about an axle (corresponding to thecrankshaft centre), which is mounted to the chassis of the beveragepreparation apparatus, preferably with the crankshaft substantially inline with the central longitudinal axis of the clamp so as to provide abalanced closing force on the clamp. As already noted, the clamp driveonly needs to apply enough force to close the clamp and to drive thepiston inwardly to compress the beverage brewing chamber of the capsulebefore and after pressurized injection of water into the clamp. Thewhole force exerted by the pressurized liquid during brewing is taken bythe locking arrangement. Therefore, the clamping mechanism itself doesnot need to exert very large forces.

The apparatus according to the present invention suitably furthercomprises an injector tube or tubes for injecting the aqueous fluid intothe interior of the capsule when the capsule is held in the brewingcavity. The injector tube is suitably made of metal, and suitably has asharpened tip to assist piercing of the freshness barrier of the capsulenozzle. The injector tube may be inserted into a nozzle on the top ofthe capsule as described in GB-A-2121762. Suitably, the apparatusfurther comprises a mechanism to move the injector into the capsuleprior to the start of brewing, and out of the capsule once brewing iscomplete. The mechanism may be actuated by closing and opening of thefirst clamp member, or it may be actuated by separate, mechanical orelectromechanical devices. The injector tube suitably communicates withthe source of pressurized water through a check valve, such as a ballvalve, that opens under pressures greater than for example about 5 barto allow water to pass through the tube under pressure but that blocksdripping of water from the injector tube when it is not in use, e.g. dueto thermal expansion of water during warm-up of the brewer. Suitably, anO-ring is mounted around the injector tube for forming a pressure-tightseal with an inlet nozzle of the capsule as described further below. TheO-ring may be held in place by a flange or sleeve fixed to the injectiontube above and abutting the O-ring.

The apparatus comprises a pump for supplying water to the injector tubeat pressures greater than 5 bar gauge, for example at 10-15 bar gauge. Atypical pump is a shuttle pump that operates at fixed displacement andfixed speed, whereby the water flow rate decreases as the back pressureincreases up to a maximum pressure of typically about 16 bar. Suitably,the apparatus further comprises a heater to supply an aqueous brewingmedium such as hot water or steam, suitably hot water at a temperatureof suitably about 80 to about 100° C. to the pump.

The apparatus of the invention may further comprise a cup receivingstation for locating a cup to receive beverage prepared in the clampassembly, wherein said cup receiving station comprises a cup detectionapparatus comprising an infrared transmitter and an infrared receiverlocated such that a cup positioned in the receiving station interruptsan infrared beam between said infrared transmitter and said infraredreceiver to detect the presence of a cup in the cup receiving station,wherein the apparatus control and user display are programmed to performthe following steps when the cup detection apparatus does not detect acup in the cup receiving station: (a) interrupt beverage preparation,and (b) prompt the user to perform one of the following options: either(i) insert a cup into the cup receiving station, or (ii) override thecup detection function.

The cup receiving station is normally situated directly below the bottomof the pack outlet in use, i.e. below the outlet of the clamp chamber,so that beverage drops under gravity into the cup. The cup receivingstation may comprise a shelf for supporting a cup. The vertical heightof the shelf may be adjustable to accommodate cups of different sizes.Alternatively, the shelf may be at a fixed vertical height below thebottom of the pack outlet but movable so that it can be displaced awayfrom the drink vending position. This allows the shelf to be optionallyused depending on the size of the cup into which the beverage will bedispensed, larger cups being able to forgo the use of the shelf and beplaced on the base of the cup receiving section directly below thebottom of the pack outlet.

The infrared cup detector is well known in the art and will not bedescribed further. The present inventors have found that a drawback ofsuch IR cup detectors is that they can fail to detect glass cups becauseof the transparency of glass to infrared radiation. This can be overcomeby providing the user interface with the option to override the cupdetect function and continue with beverage preparation if, for example,a glass cup is being used that gives a false negative output from the IRcup detect.

The apparatus may comprise a pressure sensor to measure the pressure inthe liquid inlet line to the capsule in the clamp (the back pressure).The apparatus may further comprise control elements to vary the pumpoutput and/or the configuration of the outlet channel region of theclamp in response to the measured back pressure, for example to maintaina substantially constant back pressure during beverage preparation.

The apparatus preferably comprises a second clamp assembly for holding asecond capsule, an injector for injecting water into a capsule heldinside the clamp assembly; and a pump for pumping said water throughsaid injector at a pressure less than about 1 bar gauge. The secondclamp and injector may, for example, be similar to those described inthe aforementioned patent specifications GB-A-2121762, GB-A-2122881,EP-A-0179641, EP-A-0247841 and WO-A-9905044. In this way a singleapparatus has clamps adapted, respectively, for high-pressure andlow-pressure beverage preparation. Suitably, the first and second clampassemblies are in a single housing with a single control system anddisplay associated therewith.

Suitably, the apparatus may comprise a control system and displayprogrammed to prompt a user to carry out the following sequential steps:

-   -   (a) select a beverage to be prepared;    -   (b) insert a capsule into the appropriate clamp; and    -   (c) wait while a beverage is prepared from the capsule;

Typically, the prompt (a) directs the user to select from variousbeverage options, such as filter coffee, filter tea, espresso coffee, ortwo-component beverages such as cappuccino coffee.

The prompt to select a beverage may be by means of one or more menuselection screens accessed by soft keys. The apparatus may also beprogrammed to prompt the user to provide a payment before or after saidstep (a). The payment may be by means of a coin-freed mechanism, or acard swipe, or some other automatic debiting procedure provided in thesystem.

The display may show a welcome screen, such as a logo or a picture of acup of coffee, when not in use. The apparatus may also be programmed toprompt the user to place a receptacle in the cup receiving station ofthe apparatus before said step (a). As noted above, the apparatus maycomprise a cup-detect interlock, for example an infrared detectorinterlock, to block or interrupt the operation of the apparatus if thereis no receptacle in a beverage receiving position in the apparatus. Thecontrol system may be adapted to provide a prompt to the user to inserta cup (or to override the cup detection, as described above) if no cupis detected in the cup receiving station at any stage of the procedure.

The control system and display may comprise for example a liquid crystaldisplay and soft key controls. In addition or as an alternative tovisual prompts on the display screen, the prompt (b) may includemechanically opening the appropriate clamp to permit insertion of acapsule. The prompt (b) may include a visual prompt on the display toselect a capsule of the type appropriate for that clamp (i.e. ahigh-pressure capsule according to the present invention for ahigh-pressure beverage such as espresso coffee, or a conventional FLAVIAcapsule for a low-pressure beverage for preparation in the low-pressureclamp). In this way, the user is instructed to place the capsule in therelevant clamp, avoiding any confusion in relation to where the capsuleshould be placed to progress the brewing process.

A prompting function is of general applicability to beverage preparationapparatus with multiple positions into which the capsules can be placed.The process of exposing the appropriate opening, i.e. opening theappropriate brewing section door, intuitively directs the user to placethe capsule in the required position for the chosen beverage.

Alternatively or additionally, the beverage making apparatus may furtherprovide a prompt after prompt (c), to perform the following step: (d)transfer receptacle from a beverage receiving station below the secondclamp assembly to a beverage receiving station below the first clampassembly. This prompt would be appropriate, for example, if atwo-component beverage is being prepared for example a cappuccino-typebeverage comprising a hot foamed dairy component prepared in the secondclamp assembly from a whitener/milk capsule, to which is then added ashot of espresso coffee prepared from a coffee capsule in the firstclamp assembly.

Thus, in these embodiments, the beverage making apparatus may comprise acontrol system and display programmed to prompt a user to carry out thefollowing sequential steps in response to a command to brew amulticomponent beverage:

-   -   (a) insert a first capsule containing a first beverage brewing        ingredient into one of the clamps;    -   (b) wait while a first beverage component is brewed from the        first capsule;    -   (c) transfer the receptacle from the cup receiving station of        the said one clamp to the cup receiving station of the other        clamp    -   (d) insert a second capsule containing a second beverage brewing        ingredient into the holder of the other clamp; and    -   (e) wait while a second beverage component is brewed from the        second capsule.

The apparatus is also capable of preparing both beverage components in asingle clamp, for example if the clamp assembly according to theinvention has an outlet region that can be adjusted to provide a largeropening resulting in low back-pressure in the ingredient chamber forpreparation of filter coffee or foamed milk components, followed by asmaller opening to provide a high back-pressure for preparation of anespresso coffee shot. In these embodiments the control system anddisplay are programmed to prompt a user to carry out the followingsequential steps in response to a command to brew a multicomponentbeverage:

-   -   (a) insert a first capsule containing a first beverage brewing        ingredient into the clamp;    -   (b) wait while a first beverage component is brewed from the        first capsule;    -   (c) insert a second capsule containing a second beverage brewing        ingredient into the holder; and    -   (d) wait while a second beverage component is brewed from the        second capsule.

In all of the above embodiments, the beverage making apparatus mayfurther provide a final prompt to perform the following step: removereceptacle containing the beverage from the apparatus.

When the beverage preparation apparatus comprises two clamp assemblies,it is preferable that the two clamp assemblies are configured to bepowered by a single power inlet into the apparatus. This maintainssimplicity for the user and minimises problems of separate powersupplies drawing current simultaneously from a plurality of the user'spower outlets.

When the beverage preparation apparatus comprises two clamp assemblies,it is preferable that the two clamp assemblies are configured to shareone water tank. This reduces the complexity of the device and maintainsa smaller form factor.

The beverage preparation apparatus suitably further comprises amechanical ejection means for ejecting capsules from the holder afterwater injection is complete. Suitably, the capsules are ejected into abin inside the apparatus.

The beverage preparation apparatus according to the invention mayfurther comprise an air pump and associated conduits and one or morevalves under the control of the apparatus control for injecting air intothe capsule after beverage preparation to dewater the capsule.

Suitably, the beverage making apparatus according to any of theembodiments above further comprises a water jet-forming nozzle suppliedby one of the pumps for directing a jet of water into a liquid in areceptacle in the cup receiving station of one or both clamps to foamthe liquid by high-shear mixing of air and liquid when it hits thesurface of a liquid in a receptacle. The internal cross sectional areaof the jet-forming outlet of the nozzle is generally from about 0.2 toabout 3 mm², preferably from about 0.4 to about 2 mm², for example about1 mm². Since water is substantially incompressible and not significantlyviscoelastic, it follows that a circular water jet is produced having adiameter of from about 0.5 to about 2 mm, preferably from about 0.7 toabout 1.5 mm.

Details of such jet-forming nozzles and their use to produce foamedbeverages are described in WO-A-02/087400, the entire content of whichis incorporated herein by reference.

The jet-forming nozzle may also be used to stir the beverage at anystage of the beverage preparation procedure by applying a short durationjet to swirl the liquid in the receptacle. Thus, for example, such a jetmay be used to stir the beverage as a final step in the beveragepreparation procedure. This provides further beverage preparationoptions. For example, in the conventional cappuccino process, the foamedmilk is produced in the cup as described above. This is normally done ina low-pressure brewing clamp. A shot of espresso is then deposited intothe cup from the high pressure clamp as described above. This produces acappuccino having a distinct, dark coffee layer at the bottom, and adistinct, pale and milky layer above. Some consumers prefer thisdistribution, especially for visual appeal in a glass cup. However,other consumers prefer a fully mixed “latte” of uniform colour.Therefore, the control system and user display of the apparatus of thepresent invention suitably includes an option for the user to selectcappuccino or latte. If either of these selections is made, then theprompted two-pack brewing sequence is described above is followed. Iflatte is selected, then the process includes a further step of injectinga jet of water into the cup after deposition of the coffee shot to swirlthe liquid in the cup to mix the layers uniformly.

The jet-forming nozzle may be formed from an elastomer material, such assilicone. This ensures that the jet forming-nozzle has a degree offlexibility, which assists cleaning and resists the build-up ofdeposits, such as limescale. The beverage preparation apparatus may beconfigured so that the jet-forming nozzle is periodically manipulated aspart of the apparatus' regular operation. This manipulation moves thenozzle, preferably in a sudden manner, helping to dislodge any depositsthat may build-up over time. A regular operation that simultaneouslymanipulates the jet-forming nozzle may be the removal of the bin thatcollects the waste capsule. The bin removal operation is not part of thebeverage brewing process and so the dislodged deposit will notinadvertently be incorporated into a prepared beverage.

In a further aspect, the present invention provides a beveragepreparation system comprising a beverage preparation apparatus accordingto the present invention, and further comprising a plurality of beveragepreparation capsules, preferably according to the present invention, foruse in the apparatus. Suitably, the plurality of capsules containdifferent beverage preparation ingredients, respectively. Where theapparatus is adapted for both high pressure and low pressure brewing,for example the embodiments described above with two clamp assemblies,suitably the capsules include different capsules specifically adaptedfor high pressure and low pressure brewing, respectively.

Preferably, beverage preparation in the beverage preparation apparatusand system described herein is effected by dry-opening of the capsulesduring preparation of the beverage. The beverage preparation capsulesdescribed herein are preferably adapted for dry-opening. As used herein,the term “dry-opening” means that the capsules are opened by airpressure rather by direct liquid pressure, i.e. that the afore-mentionedregion of the bonding in the bottom edge of the capsule which isreleasable to allow escape of beverage from the capsule during beveragepreparation is ruptured by air pressure rather than direct liquidpressure. During beverage preparation pressurised water is injected intothe capsule via an injector, and the term “dry-opening” means that whenpressurised water is injected into the capsule or into the injector orinto the pipework which feeds the injector with pressurised water fromthe water reservoir, the residual air present in the capsule and/orinjector and/or said pipework is forced against the inside of the bottomedge of the capsule such that it is said residual air under the pressureof the pressurised liquid, rather than the pressurised liquid itself,which ruptures the bottom edge of the capsule before the pressurisedwater comes into contact therewith. The opening of the capsule by airpressure, rather than by direct liquid pressure, advantageously resultsin a cleaner opening of the capsule, avoiding any uncontrolled liquidspray during the opening of the capsule. The dry-opening of the presentinvention is associated with a distinctive popping sound.

Alternatively, the capsules may be opened by the presence of theinjected liquid at the bottom edge of the capsule. In particular, thecapsule opening may be caused by the heat and/or pressure of the liquidat the bottom edge.

Suitably, the system comprises both capsules according to the invention(e.g. for preparing espresso shots) and capsules not according to theinvention, for low pressure beverage preparations such as filter coffee,filter tea, or hot foamed milk for subsequent addition to an espressoshot to form a cappuccino. The capsules not according to the inventionare suitably made in accordance with one of the FLAVIA patentsidentified above. The hot foamed milk capsules suitably contain a solidor liquid milk concentrate for example as described in detail inWO-A-02/087400.

Since it is undesirable for a low pressure capsule to be used in a highpressure clamp, and vice versa, the apparatus suitably comprises meansto ensure that only the right kind of capsule is used in each clamp.

For example, the beverage making apparatus may further comprise acapsule recognition device in the or each clamp assembly operativelyassociated with the control system and the display of the apparatus. Atits simplest, this device may be a simple bimodal detector, such as asource of UV light and a light detector, for detecting whether afluorescent region is present on a capsule. More complex capsulerecognition devices such as bar code readers or RFID chip detectors arealso contemplated. Alternatively or additionally, the capsules may beidentified by the use of differently coloured plastics for the capsulenozzles. For example, the capsules for high pressure brewing may containnozzles formed from a black plastic, whereas the capsules for lowpressure brewing may contain nozzles formed from white or translucentplastic. In these embodiments the apparatus clamps further comprise alight source and light detector for detecting the colour of the capsulenozzle, and the control is programmed to interrupt the beveragepreparation process if the wrong type of capsule is inserted in a clamp.

The primary purpose of the capsule recognition device is to determinewhether the right type of capsule has been inserted into the clamp, i.e.a high-pressure capsule of the kind described in accordance with thepresent invention for a high pressure brewing clamp, or a low pressurecapsule such as the conventional FLAVIA type capsules for a low pressureconfiguration clamp. If the recognition device determines that the wrongtype of capsule has been inserted, then the control system is programmedto prompt the user to change the capsule. The recognition device mayread further information from the capsule relating to the capsuleingredients and the control system then adapts the brew cycle parameterssuch time/temperature/water volume to optimize the product for thatingredient.

Alternatively or additionally, the first clamp may incorporate a firstkey way and said second clamp comprises a second key way different fromsaid first key way, and wherein a first capsule comprises a first nozzleconfiguration that permits insertion of the first capsule into the firstclamp through the first clamp key way but not into the second clampthrough the second clamp key way element, and the second capsulecomprises a second nozzle configuration that permits insertion of thesecond capsule into the second clamp through the second clamp key wayelement but not into the first clamp through the first key way.

In a further aspect, the present invention provides a method of making abeverage comprising inserting a beverage preparation capsule accordingto the invention into the clamp assembly of a beverage preparationapparatus according to the present invention such that the outletchannel of said capsule is pinched between the clamp members in saidoutlet region; injecting an aqueous liquid into said capsule in saidinlet region to produce a beverage in said capsule; and allowing saidbeverage to escape through the outlet channel and downstream chamber.

The bottom of the capsule extends through the bottom of the clamp,whereby the beverage exiting the capsule does not contact the clamp.This substantially eliminates cross-contamination between successivebeverages prepared in the same clamp.

The pressure pads extending along the inner wall of the chamberenclosing the capsule contact and compress the beverage preparationcapsule when the clamp is closed around the capsule. The compressed bedof coffee (or other ingredient) inside the capsule is profiled by thebuffer pads and this has been found to improve the quality of the finalbeverage, in particular the total extracted solids. This improvement isthought to be due to a reduction in channelling of liquid through theprofiled ingredient bed inside the capsule. A further advantage of thepressure pads is that they allow the same clamp to be used for capsulescontaining different amounts of ingredient. Typically, systems of thistype use capsules having identical dimensions but containing differentamounts of ground coffee to make products of different volumes orstrengths. The buffer pads enable the clamp effectively to compresscapsules containing a range of different ingredient amounts.

The capsule may be preheated by a heater within the clamp assemblybefore and during beverage preparation. A hollow needle is insertedthrough the inlet region in the top of the clamp assembly and into thenozzle bore of the capsule to pierce the membrane seal, and hot water isinjected at a pressure of approximately 10 bar gauge to brew coffeeinside the capsule. It has been found that the pressure increase insidethe capsule caused by the injection of water results in an increase inair pressure in the bottom of the capsule causing the bottom seal of thecapsule to rapidly rupture allowing the opening of the capsule outlet ina dry manner, before the liquid reaches the bottom of the capsule. Thishas the advantage of a cleaner opening action compared to a processwhere the liquid is directly responsible for the capsule outlet openingaction.

When a pinch is applied to the outlet channel of the capsule asdiscussed above, the pinch force is just sufficient to permit theresulting beverage to escape through the outlet channel at the desiredrate while maintaining high pressure inside the capsule, withoutexcessive build-up of back pressure in the ingredient chamber.

Suitably, the aqueous fluid is injected at a pressure of from about 5 toabout 15 bar gauge, for example about 10 bar gauge. Typically, theaqueous fluid is injected at a temperature of from about 88° C. to about98° C., for example about 90° C. The liquid may be injected into thecapsule at an average rate suitably from about 25 ml/min to about 500ml/min and more preferably from about 50 to about 150 ml/min. Theduration of the water injection is suitably from about 10 to about 30seconds, for example about 12 to about 15 seconds. Suitably, the aqueousfluid consists essentially of water and the brewing ingredient comprisesground coffee. This enables espresso-type coffee to be produced.

The liquid may be injected in intermittent or pulsed fashion to optimisethe organoleptic properties of the product. The method may furthercomprise the step of injecting air into the capsule after brewing toexpel residual beverage from the capsule. Alternatively or additionally,dewatering of the residue may be achieved by compressing the ingredientbed after brewing by moving the elastomeric clamp wall inwardly asdescribed above. A similar compression of the ingredient (e.g. groundcoffee) bed is suitably performed before water injection to consolidatethe ingredient bed. Experiments have shown that there is an optimumdegree of compression of the ingredient bed that gives maximum formationof espresso crema and other espresso-like characteristics in the coffee.

Suitably, substantially all steps of the method other than the selectionof beverage type, insertion of the cup into the cup station(s), andinsertion of the capsule(s) into the clamp(s) are performedautomatically by the apparatus.

The specific embodiments of the present invention shown in the drawingswill now be described in more detail.

Referring to FIGS. 5 and 6, the capsule 10 according to the presentinvention is a modification of the capsule described in WO2012175985 andshown in FIGS. 3 and 4. It comprises two flexible laminate sheets 11,12.Each laminate sheet comprises an inner thermoplastic sealing film, anoxygen-impermeable metal foil layer, and an outer printing layer. Thefront and back sheets 11,12 are bonded together along edge seams 14,15,top seam 13 and bottom seam 16. The bonding of the top and side edges issuitably by heat or ultrasonic bonding, to form a permanent weld betweenthe sheets. At least a central region 23 of the bottom seam 16 is bondedwith a pressure-sensitive, peelable adhesive that can be released by theaction of heat and/or pressure of liquid and/or air inside the capsule,and/or assisted by heat applied from outside the capsule. A nozzle 17 isinserted into the top seam 13 of the capsule. The nozzle 34 has acentral cylindrical bore and a flange at the inlet (upper) end. Theoutlet (lower) end 18 of the nozzle is lozenge-shaped in transversecross-section to assist insertion into the top edge seam 13 withairtight bonding to the front and back sheets. The cylindrical bore ofthe nozzle is sealed at the top by frangible membrane.

A further transverse permanently bonded seam 19 between the front andback sheets extends across the capsule intermediate the top and bottomtransverse seals to divide the capsule into a beverage ingredientchamber 22 and a downstream beverage collection/conditioning chamber 23.The intermediate seam 19 does not extend completely across the capsule.An unbonded gap 20 is left in the intermediate seam to provide theoutlet channel from the beverage preparation chamber.

Substantially filling the ingredient chamber 22 of the capsule there isabout 15 g of ground roasted coffee 27. The capsule provides an oxygenand moisture-impermeable enclosure for the coffee until the capsule isused.

The permanent transverse intermediate heat seal 19 further comprisescurved downward extensions 21 on either side of the longitudinal axis ofthe capsule below the outlet channel 20 defining the lateral edges ofthe downstream (outlet) chamber 23. The width of the downstream chamber23 is intermediate the width of the beverage ingredient chamber 22 andthe narrower outlet channel 20.

A filtration material in the outlet channel is provided by a single,V-folded rectangular strip 24 of nonwoven polypropylene fiber filtermaterial that is bonded across the width of the capsule. The long sideedges of the V-folded strip are bonded into the transverse intermediateseal 19, i.e. the filter strip does not extend above the intermediateseal 19. The V-folded filter strip 24 extends downwardly through theoutlet channel 20 and the outlet chamber 23, with the vertex of the Vbonded into the bottom edge seal 16 of the capsule, including theheat-releasable region 23. The outlet channel 20 is thereby filled by adouble thickness of filter sheet material. It is noted that in regionswhere the V-folded filter sheet overlaps the intermediate transverseseal, the side edge seals, and the bottom edge seal 16, the said sealbetween the front and back sheets is formed through the V-folded filtersheet so that the front and back sheets and the V-folded filter sheetare all bonded together. This is facilitated in the permanently heatsealed regions by the use of a filter sheet containing or consisting ofthermoplastic fibers, such as polypropylene fibers.

Referring to FIGS. 7 and 8, a clamp arrangement 30 of an apparatusaccording to the present invention is shown schematically. The clampcomprises a first clamp member 31 and a second clamp member. The firstclamp member 31 is formed from metal or similar rigid material with aninside surface comprising a planar periphery and a concave centralregion 33, which is optionally removable, for receiving the beverageingredient chamber of a capsule, such as those according to FIG. 5 or 6.An O-ring 34 is seated in a groove extending around the planarperiphery.

The second clamp member comprises a rigid frame 32. The rigid frame 32of metal or similar surrounds a central void. A layer of elastomer 37having a flanged periphery 42 is interference-fitted over the rigidframe 32. The surface of the layer of elastomer facing the first clampmember is profiled to define a recess having pillow pads therein asshown in more detail in FIG. 14. The opposite side of the layer ofelastomer faces a piston face 49 of a piston 36, whereby displacement ofthe piston face 49 relative to the rigid frame 32 towards the firstclamp member 31 pushes the layer of elastomer outwardly so that itbulges in the direction of the first clamp member 31.

The piston 36 comprises a piston shaft received in mating engagement inthe central void of the rigid frame 32, and a piston flange extendingperipherally from the piston shaft behind the rigid frame 32, i.e. theside of the rigid frame 32 facing away from the first clamp member 31. Acircumferentially spaced plurality of springs 35 extends between therigid frame 32 and the piston flange to allow limited resilient relativemovement of the piston member and the rigid frame 32.

Three locking pins 43 may extend from each side of the first clampmember, and three locking pins 44 may extend from each side of thepiston flange. Respective pairs of locking pins on the first clampmember and on the piston flange are aligned along the direction ofclosure of the first and second clamp members. A locking device shown indash-dot lines in FIGS. 7 and 8 is provided in the form of locking rods45 on each side of the clamp assembly, each locking rod 45 having threetransverse locking bars 46, and each said locking bar 46 having flanges47,48 at the ends thereof for engaging behind the respective pins 43,44on the first clamp member and the piston flange as shown in FIG. 8 tolock the clamp in the closed position. An actuating mechanism (notshown) moves the locking rods 45 vertically (i.e. perpendicular to theclamp direction) to lock and unlock the clamp. It can be seen that, inthe locked position shown in FIG. 8, the locking mechanism allows thepiston 36 to move towards the first clamp member 31 slightly, butprevents the first clamp member and the piston from moving apart. Theslight permitted additional movement of the piston towards the firstclamp member can be used for: (a) easy latching and unlatching of thelocking mechanism, (b) compressing (tamping) of the beverage ingredientinside the clamp prior to brewing, and (c) compressing of the beverageingredient after brewing to dewater the capsule after brewing.

It can further be seen that, in the locked position shown in FIG. 8, thesprings 35 bias the rigid frame 32 towards the first clamp member 31 toapply a sealing force around the periphery of the first clamp memberwhere it engages with the rigid frame 32 of the second clamp member.

The back of the piston 36 comprises a centrally located rear extension38 having a slot 40 in which is received a drive pin 39 of the drivemechanism. A support arm 41 extends from the rear extension 38 tosupport the piston 36 in pivoting fashion as described in more detail inrelation to FIGS. 15a to 15m . The drive pin 39 is actuated by themechanism to drive the piston 36 towards the first clamp member 31,which is fixed to the chassis of the brewer. In use, the drive pin 39and drive mechanism initially drive the second clamp member forwarduntil the peripheral region of the elastomer cover on the rigid frame 32abuts against the peripheral region of the first clamp member 31.Further forward movement of the drive pin 39 compresses the springs 35and drives the piston face 49 forward relative to the rigid frame 32.The piston 36 is driven forward beyond the position shown in FIG. 8 toforce the piston face 49 into the back of the elastomer layer 37 andthereby cause the elastomer layer 37 to bulge into the beverage brewingcavity to compress the beverage ingredient inside the capsule. Thelocking gates 45 are then dropped and the drive pin is moved back sothat the locking pins 43,44 abut against the flanges 47,48 of thelocking gates 45 to lock the clamp. The drive pin 39 is then movedfurther back, along the slot 40 as shown in FIG. 8, so that itdisengages from the piston 36 when brewing takes place inside the clampchamber to ensure that forces arising from pressure inside the clampchamber during brewing are not transmitted to the drive mechanism, wherethey could cause deformation and future misalignment. Once beveragepreparation from the capsule is complete, the drive pin 39 is movedforward again to drive the piston 36 beyond the position shown in FIG. 8to force the piston face 49 into the back of the elastomer layer 37 andthereby cause the elastomer layer to bulge into the beverage brewingcavity to compress the beverage ingredient inside the capsule to squeezeand dewater the capsule. This also disengages the locking pins 43,44from the locking gate flanges 47,48. The locking gates 45 are thenraised, and the drive pin 39 is moved back to move the second clampmember as described further in relation to FIGS. 15a -15 m.

FIG. 9 depicts details of a preferred drive mechanism that can be usedwith the clamp assembly, and preferably as an alternative to the lockingmechanism of FIGS. 7 and 8. FIG. 9 shows the clamp assembly arrangementin an open configuration. All features that are equivalent to thosedescribed in relation to the clamp assembly arrangement of FIGS. 7 and 8have the same reference numbers.

In the embodiment of FIG. 9, the drive mechanism has a crankshaft 84connected to the chassis of the brewing apparatus at a pivot point, thecrankshaft centre 86. Accordingly, the crankshaft 84 can rotate aboutthe crankshaft centre 86.

The crankshaft 84 is pivotingly connected to one end of a crank arm 88at pivot point 90, allowing rotation of the crank arm relative to thecrankshaft about this point. The crank arm 88 is then in turn pivotinglyconnected to the piston 36 at a further pivot point 92. Accordingly, thecrank arm 88 can also rotate relative to the piston 36 about the pivotpoint 92. These two pivot points 90, 92 on the crank arm 88 arepositioned at opposite ends of the crank arm 88.

The piston 36 is constrained in its movement along a direction towardthe first clamp member 31. In this arrangement, rotation of thecrankshaft 84 can therefore be used to control the linear distance ofthe piston 36 from the crankshaft centre 86, which is positionally fixedrelative to the chassis. Since, the position of the first clamp member31 is also fixed relative to the chassis prior to brewing, rotation ofthe crankshaft 84 also moves the second clamp member in relation to thefirst clamp member 31. When the pivot points are all aligned as depictedin FIG. 10, the piston 36 is at its furthest point from the crankshaftcentre 86 and at its closest point to the first clamp member 31. Theapparatus is therefore set up so that this arrangement of the drivemechanism corresponds to the clamp assembly being in the closed brewingconfiguration. The advantage of such an approach is the elimination ofany resulting torque on the crankshaft 84, even when the pistonexperiences the significant linear force from the second clamp memberassociated with the back pressure from the brewing process. Hence, thisarrangement of the drive mechanism effectively mechanically locks theclamp assembly in the closed brewing configuration ensuring the motorthat drives the rotation of the crankshaft (not shown) is not subjectedto forces that could damage it.

The beverage preparation apparatus may have a finger guard, such asillustrated in FIGS. 11 and 12, which blocks access to the clamp chamberwhen the clamp assembly is open but allows the exit of liquid from theclamp chamber when the clamp assembly is in the closed brewingconfiguration. Specifically, the finger guard may block the outlet ofthe clamp assembly. In the illustrated example, the finger guard 94 ispivotingly attached to the chassis of the brewing apparatus and isspring loaded to a blocking configuration, resting against ledge 96 ofthe chassis. When the finger guard 94 is in the blocking configuration,it is not possible for the user to access the clamping assembly fromoutside the chassis. This ensures that the user does not inadvertentlyplace any item or appendage between the first clamp member 31 and thesecond clamp member during the clamping process, avoiding the risk ofinjury to the user or damage to the clamp.

The finger guard 94 is moved to an non-blocking configuration,illustrated in FIG. 12, as part of the action of the clamping assemblymoving to the closed brewing configuration. This can be achieved by aprojection 98 on piston 36 moving towards finger guard 94 as the piston36 is moved to the closed brewing configuration. As the second clampmember contacts the first clamp member 31, the projection 98 contactsthe finger guard 94 and thus moves it to its non-blocking configurationagainst the action of the finger guard's spring. When the clamp assemblyis subsequently placed back in its open configuration by moving thesecond clamp member away from the first clamp member 31, the fingerguard 94 will automatically return to its blocking configuration underthe action of the spring.

Projection 98 is positioned to the side of the outlet from the clampchamber so that its presence does not impede the liquid exiting from theclamp chamber. Two projections may be present, one either side of theclamp chamber's outlet to provide a balanced force to the finger guard94 during the opening action.

FIG. 13 shows a schematic transverse cross-section through part of theclamp assembly 30 at the location of the capsule outlet channel 20 inuse. It can be seen that the transverse sealed region 19 and the outletchannel 20 of the capsule are pinched between the first clamp member 31and the elastomeric layer 37 covering the rigid frame 32 of the secondclamp member. A shallow recess 50 is present in the first clamp memberin the region of the outlet channel 20, whereby the pinch is justsufficient to maintain the desired back pressure inside the capsuleingredient chamber during beverage preparation while allowingsufficiently rapid flow of the beverage through the outlet channel.

FIG. 14 shows a front perspective view of the rigid frame 32 andelastomer cover 37 of the second clamp member. The rigid frame 32 issubstantially rectangular, and dimensioned to fit around the beverageingredient chamber of the capsule. The elastomer cover 37 is molded inone piece from a silicone elastomer. It comprises a peripheral flange 42that fits tightly around the rigid frame 32 to secure the cover on theframe while permitting easy removal for replacement when necessary. Thefront (capsule facing) face of the elastomer cover 37 comprises agenerally planar periphery 53 for abutment against the periphery of thefirst clamp member 31. In use, the periphery of the capsule is pinchedbetween this periphery 53 of the elastomer cover 37 and the periphery ofthe first clamp member 31. A bottom region of the elastomer cover 37periphery pinches the outlet channel 20 of the capsule 10. A top regionof the elastomer cover periphery includes a shallow V-shaped recess 58to receive the portion of the top edge of the capsule 10 having therhomboidal nozzle body inserted therein.

The central region 54 of the front face of the elastomeric cover 37 isgenerally concave to receive one side of the capsule 10. However, threepillow-shaped projections 55,56,57 extend upwardly from the concavesurface to provide improved compaction of the beverage ingredient, inparticular ground coffee, inside the capsule and to improve liquid flowthrough the ingredient bed during brewing, as described herein.

Referring to FIGS. 15a to 15m , certain mechanisms of a beverage makingapparatus 60 according to the present invention are shown schematically.The apparatus 60 comprises a rigid chassis 61 having metal side platesbetween which most of the components of the apparatus are arranged. Thefirst (front) clamp member is mounted on a door 62 that is attached tothe chassis by a pivot 63 near the bottom of the door that allows thedoor to swing open as shown in FIG. 15b when a locking mechanism 65 isdisengaged. This pivoting motion may be actuated by a motor. Closing ofthe door 62 by the same motor may be actuated by the user pushing thedoor 62 slightly towards the closed position after insertion of thecapsule has been performed as shown in FIG. 15c . Once the door 62 isclosed, the door lock mechanism 65 is engaged automatically as indicatedin FIG. 15d to secure the top of the door to the chassis 61 so that thedoor and the first clamp member do not move relative to the chassis 61during beverage preparation.

The apparatus of FIG. 15 further comprises a second clamp member 64 ashereinbefore described. The second clamp member and piston arrangement64 is mounted on a rigid swing arm 79 having a proximal end rigidlyattached to the piston, and a distal end pivotally attached to thechassis 61 through an axle 66 extending across the chassis above theposition of the second clamp member when in the closed brewingconfiguration. The piston, as hereinbefore described, has a rearextension having a slot therein projecting from the back of the pistonshaft. A drive pin 67 for driving the piston is inserted through theslot such that it can move freely in the slot. The drive pin 67 ispivotingly attached to a proximal end of a crank arm 68. The distal endof the crank arm is attached to a crankshaft 70 by a pivot 69. Thecrankshaft 70 is mounted on an axle 72 rotatably mounted on the chassis61. The circular peripheral part 70 a of the crankshaft is toothed, forengagement with a toothed drive wheel 73 of an electric motor alsofixedly mounted to the chassis 61.

After loading of the capsule into the machine, and locking of the doorand front clamp member as shown in FIG. 15d , the motor is actuated torotate the crankshaft 70 to the maximum extent, whereby the crank arm 68and drive pin 67 drive the piston and second clamp member arrangement 64to close the clamp assembly as shown in FIG. 15e . The rigid framecovered with the elastomeric layer is brought into abutment with thefirst clamp member, and the piston is then driven 1-15 mm beyond theclosed brewing configuration of the piston in order to compact theingredient inside the capsule by forcing the elastomeric layer of thesecond clamp member into the brewing cavity, as described above. Thegate mechanism 76 is then actuated as shown in FIG. 15f to drop thegates (not shown) as described in relation to FIGS. 7 and 8 above. Theelectric motor is then briefly actuated in the reverse direction toreturn the crankshaft 70 and the crank arm 68 to the position shown inFIG. 15g . This brings the locking pins on the clamp members intoabutment with the gate flanges as described above, whereby the firstclamp member, second clamp member and piston are locked in the closedbrewing configuration. Also, as seen in FIGS. 8 and 15 g, the drive pin67 is retracted slightly in the slot on the back of the piston. Thisensures that no load is applied to the drive pin 67 during beveragepreparation inside the clamp chamber. The clamp assembly is now readyfor preparation of the beverage inside the capsule.

The apparatus further comprises a water injection tube 78 as shown inFIG. 15g . Following locking of the clamp, an actuator mechanism movesthe water injection tube 78 downwardly to pierce the freshness seal ofthe capsule nozzle and form a mating seal within the capsule nozzle.Water is then pumped into the capsule 10 from a tank 80 by a shuttlepump 81 at about 10 bar pressure, as shown in FIG. 15h , to prepare thebeverage inside the capsule. The beverage flows out from the bottom ofthe capsule 10 into a cup 82 located in a cup receiving station of theapparatus below the clamp.

When the water injection is complete, the motor is actuated brieflyagain in the forward direction to drive the crank arm 68, drive pin 67,and thereby the piston in the direction of closure as shown in FIG. 15i. This causes the elastomeric layer on the second clamp member again tobulge into the capsule chamber, thereby squeezing the capsule to expelfurther beverage from the capsule (this is also referred to asdewatering the capsule). This motion of the piston also releases thelocking pins on the piston and the first clamp member from abutment withthe locking gates. The locking gates are then lifted as shown bymovement of the mechanism 76 in FIG. 15j , and the injection tube isretracted. The motor is then actuated in the reverse direction to swingthe second clamp member away from the first clamp member as shown inFIG. 15k . This opens the back of the clamp and allows the capsuledisposal mechanism (not shown) to fling the spent capsule into a bin 74inside the apparatus, as shown in FIG. 15l . The apparatus is then inthe condition shown in FIG. 15m , ready for removal of the cup 82containing the beverage after which the process can be repeated. It willbe appreciated that the substantially the same sequence can be utilisedwhen the clamp chamber is locked using the top dead centre arrangementof the drive mechanism, rather than the locking mechanism of FIGS. 7 and8.

FIG. 16 shows a schematic partial view of a beverage preparationapparatus 200 according to the invention. The apparatus 200 comprises aclamp assembly 30 similar to that described above in relation to FIGS. 7and 8. The first (front) clamp member is pivoted at the bottom by apivot that allows the first clamp member to swing outwardly for loadingof a capsule 10 according to the invention into the clamp. The capsule10 is loaded into the clamp by inserting the nozzle of the capsulethrough a key way 214 in the front of the apparatus. After passingthrough the key way 214, the capsule nozzle slots into the positionshown in FIG. 16 in which the flange of the capsule nozzle rests on asupport 212 having a slot through which the nozzle tube extends. Theoutlet channel 20 from the beverage ingredient chamber of the capsule ispinched by the bottom of the clamp assembly. The outlet chamber 20 andreleasable bottom edge seal 23 of the capsule extend below the clampassembly, thereby ensuring that there is no contamination of the clampby the beverage during the preparation and dispensing process. Theapparatus 200 may further comprise a heat source (not shown), such as ahot air or radiant heat source, located adjacent to the releasablebottom edge seal 23 of the capsule below the clamp to heat thereleasable bottom edge seal 23 to assist opening of the capsule.

The clamp assembly 30 further comprises a second clamp member andlocking elements as hereinbefore described. The sequence of the drivemechanism for the second clamp member is described above in relation toFIGS. 15a to 15 m.

The apparatus of FIG. 16 further comprises a cup receiving stationsituated below the clamp, in the form of an alcove having a shelf 204for supporting the cup 82. An infrared transmitter 206 and an infrareddetector 207 are situated on opposite sides of the alcove, whereby thepresence of a cup 82 in the cup receiving station interrupts theinfrared beam between the transmitter 206 and the receiver 207 toprovide a cup detection function. A disposal bin 74 is also providedinside the apparatus for receiving spent capsules 10 after beveragepreparation. The apparatus according to this embodiment furthercomprises a mechanism (not shown) to fling the spent capsules 10 intothe bin 74 after beverage preparation is complete and after retractionof the second clamp member. This mechanism may be similar to thecorresponding mechanism used in existing FLAVIA beverage machines.

The apparatus 200 further comprises a liquid injection tube 78 in theform of a metal tube having a sharpened tip for piercing through thefreshness barrier into the bore of the capsule nozzle to inject waterinto the capsule. The injection tube 78 forms a mating fit inside thebore of the capsule nozzle. The injection tube 78 is further providedwith an O-ring 213 fitted around the tube and retained under a flange211 on the injection tube. In use, the O-ring seats against the top ofthe capsule nozzle flange to form a pressure-tight seal between theinjection tube and the capsule nozzle. The injection tube 78 is mountedon a reciprocating mechanism 210 to move the injection tube downwardlyinto the capsule nozzle prior to and during beverage preparation, andupwardly out of the way during capsule insertion and disposal.

The apparatus further comprises a jetting nozzle 208 for jetting waterinto the receptacle 82 in the cup receiving station. The jetting nozzle208 is located slightly above the top of the receptacle, and at an angleto the vertical so that a jet of water from the nozzle swirls liquidinside the cup. The jetting nozzle may be a nozzle having a taperedinternal bore, for example substantially as described in GB-A-2379624.

The apparatus further comprises a water tank 216 (which may be heated),a shuttle pump 217 capable of delivering water at pressures of 10-15bar, and a hot block heater 218 for heating the pressurized water to thedesired temperature of 90-100° C. Downstream of the hot block heater 218the water conduit bifurcates into a first conduit leading through avalve 220 to the injection nozzle 78 of the clamp arrangement, and asecond conduit leading through a valve 221 to the jet nozzle 208 forin-cup foaming or stirring. The apparatus may further comprise an airpump (not shown) for supplying air under pressure to either theinjection tube conduit and/or to the jet nozzle conduit through suitablevalves. The compressed air can be injected into the capsule afterbrewing to dewater the capsule after brewing. Alternatively oradditionally, the pressurized air can be injected into the capsulebefore brewing to open the capsule immediately before water injection.Alternatively or additionally, the pressurized air can be used to clearthe water conduits of liquid to eliminate drips and to prevent thebuild-up of scale in the water conduits.

The apparatus of FIG. 16 further comprises a control system 224 and auser interface 226. The control system 224 controls the pump 217, theheater 218, the valves 220,221, the clamp assembly opening and closingmechanisms, any hot air supply and valves, the capsule disposalmechanism, etc., in the sequences described herein to produce thedesired beverages. The user interface 226 suitably comprises a displayand appropriate soft keys or touch screen controls to enable the user toselect the desired beverage and initiate the process.

Referring to FIGS. 17a and 17b , a first key nozzle 230 for a capsuleaccording to the present invention comprises a rhomboidal base 234, atubular shaft 242, and a top flange made up of a first portion 235shaped as a hexagonal prism, and an upper, second portion 236 that islozenge-shaped. These components are suitably formed integrally byinjection molding or 3D-printing. In the assembled capsule, therhomboidal base is inserted and bonded between the front and back sheetsof the capsule in the top edge of the capsule. A tubular bore 233extends through all of these components for receiving the waterinjection tube of the brewer in use. The bore 233 is sealed by atransverse freshness barrier 237, which may be molded integrally withthe other components of the nozzle as a frangible barrier, or may be amembrane of different material bonded across the top of the bore.

Referring to FIGS. 18a and 18b , a second key nozzle 240 for a capsuleaccording to the present invention comprises a rhomboidal base 244, atubular shaft 242, and a flange 245 shaped as a hexagonal prism. Thesecomponents are suitably formed integrally by injection molding or3D-printing. In the assembled capsule, the rhomboidal base 244 isinserted and bonded between the front and back sheets of the capsule inthe top edge of the capsule. A tubular bore 243 extends through all ofthese components for receiving the water injection tube of the brewer inuse. The bore is sealed by a transverse freshness seal 247, which may bemolded integrally with the other components of the nozzle as a frangiblebarrier, or may be a membrane of different material bonded across thetop of the bore. The hexagonal prism flange 245 of the nozzle of FIGS.18a and 18b is thicker when measured along the principal axis of theprism than the hexagonal prism flange of the nozzle of FIGS. 17a and 17b.

FIGS. 19a and 19b show transverse cross sections through first andsecond key ways 250,260 on first and second brewer clamp assemblies forreceiving capsules having nozzles in accordance with FIGS. 17a and 17b ,and FIGS. 18a and 18b , respectively. It can readily be seen that thenozzles 230 of FIGS. 17a and 17b will fit through the key way 254 ofFIG. 19a but not through the key way 260 of FIG. 19b . Likewise, thenozzles 240 of FIGS. 18a and 18b will fit through the key way 260 ofFIG. 19b but not through the key way 250 of FIG. 19a . Suitably,capsules for use in the high pressure brewing clamps as described hereinhaving an outlet channel pinched by the clamp are provided with a firstkey nozzle type, and capsules for use in low pressure brewing clampshaving a larger outlet channel, such as conventional FLAVIA capsules foruse in conventional FLAVIA type brewing clamps, have a second key nozzletype, whereby the key ways associated with the respective clamps preventmisuse of capsules.

It will be appreciated that, for economy of the description, thepreferred and alternative features have in some cases been described inrelation to only one aspect of the invention even though they areapplicable to all of the other aspects. Accordingly, any feature thathas been described above in relation to any one aspect of the inventionmay also be applied to any other aspect of the invention.

The above embodiments have been described by way of example only. Manyother embodiments falling within the scope of the accompanying claimswill be apparent to the skilled reader.

The invention claimed is:
 1. A beverage preparation apparatus forpreparing a beverage by injection of pressurized water into a capsulehaving at least one flexible wall, said beverage preparation apparatusincluding a clamp assembly operable between an open configuration and aclosed brewing configuration for beverage preparation, said clampassembly comprising: a first clamp member having a recess in an innerwall thereof for receiving part of the capsule; a second clamp membercomprising a rigid peripheral frame having a central void, and aresilient layer extending across said central void, whereby a frontsurface of said resilient layer defines a second inner wall forreceiving part of the capsule, wherein respective inner walls of saidfirst and second clamp members in said closed brewing configurationdefine a chamber for enclosing and supporting the capsule duringbeverage preparation; and a piston positioned in the central void of therigid frame, said piston comprising a piston face for abutting a backsurface of said resilient layer and a piston body, wherein said pistonis resiliently coupled to said rigid peripheral frame to allow limitedresilient movement of said rigid frame relative to said piston along adirection of closure of the clamp assembly.
 2. The beverage preparationapparatus according to claim 1, wherein the clamp assembly furthercomprises a securing mechanism operable between an unlockedconfiguration and a locked configuration for locking the first clampmember in the closed brewing configuration.
 3. The beverage preparationapparatus according to claim 1, wherein said clamp assembly furthercomprises a drive mechanism coupled to the piston for driving the secondclamp member into the closed brewing configuration against the firstclamp member.
 4. The beverage preparation apparatus according to claim3, wherein said drive mechanism comprises a crankshaft and a crank arm,said crankshaft rotating about a crankshaft centre and said crankshaftbeing pivotingly connected to a first end of said crank arm at a firstpivot point, and said piston being pivotingly connected to a second endof said crank arm at a second pivot point.
 5. The beverage preparationapparatus according to claim 4, wherein said crankshaft is a toothedcrankshaft having a crank axle and said crank axle is mounted to thechassis of the apparatus and extends substantially perpendicular to thedirection of closure of the clamp, and wherein the toothed crankshaft isdriven by a toothed drive wheel coupled to an electric motor.
 6. Thebeverage preparation apparatus according to claim 1, further comprisinga locking mechanism for securing the first clamp member to the secondclamp member in the closed brewing configuration when the lockingmechanism is in a locked position.
 7. The beverage preparation apparatusaccording to claim 6, wherein said locking mechanism permitsdisplacement of the piston towards said first clamp member when thelocking mechanism is in the locked position.
 8. The A beveragepreparation apparatus according to claim 1, wherein said piston issupported on an arm that is pivotingly connected to a chassis of theapparatus whereby said piston can be swung away from said first clampmember about an axis substantially perpendicular to the direction ofclosure of the second clamp member.
 9. The beverage preparationapparatus according to claim 1, wherein said front surface of saidresilient layer comprises a concave base surface for receiving saidcapsule and one or more pressure pads projecting from said concave basesurface for selectively constricting one or more regions of the capsuleheld in the second clamp member.
 10. The beverage preparation apparatusaccording to claim 1, wherein said piston comprises a peripheral flangebehind the rigid frame, and said resilient coupling between the pistonand the rigid peripheral frame comprises a plurality of springs spacedaround the rigid peripheral frame and the peripheral flange of saidpiston, whereby relative movement of the piston towards or away from therigid frame respectively compresses or extends the springs.
 11. Thebeverage preparation apparatus according to claim 1, further comprising:a cup receiving station for locating a cup to receive a beverageprepared in the clamp assembly, and a water jet nozzle located above thecup receiving station to direct a jet of water into the cup in the cupreceiving station.
 12. The beverage preparation apparatus according toclaim 1, further comprising a control system and a user display, whereinthe control system and user display are programmed to offer a user achoice between a homogeneous beverage such as latte and an inhomogeneousbeverage such as cappuccino, and to inject water into the beverage inthe cup after beverage preparation in the clamp assembly to swirl andmix the beverage in the cup in response to a command to prepare ahomogenous beverage.
 13. The beverage preparation apparatus according toclaim 1, further comprising a capsule recognition device and a controlsystem and a user display programmed to interrupt beverage preparationand to indicate to a user when a capsule of the wrong type has beeninserted in the clamp assembly.
 14. The beverage preparation apparatusaccording to claim 1, further comprising a cup receiving station forlocating a cup to receive beverage prepared in said clamp assembly,wherein said cup receiving station comprises a cup detection apparatuscomprising an infrared transmitter and an infrared receiver located suchthat a cup positioned in the cup receiving station interrupts aninfrared beam between said infrared transmitter and said infraredreceiver to detect the presence of the cup in the cup receiving station,wherein a control system and a user display are programmed to performthe following steps when the cup detection apparatus does not detect acup in the cup receiving station: (a) interrupt beverage preparation,and (b) prompt the user to perform one of the following options: either(i) insert a cup into the cup receiving station, or (ii) override thecup detection function.
 15. The beverage preparation apparatus accordingto claim 1, further comprising an injector tube for injecting water intothe capsule held inside the clamp assembly, and a pump for pumping saidwater through said injector at a pressure greater than about 5 bargauge.